NSR250 rebuild - 'The ELF Special'

[Wil_K]

Thought I should share one of my current projects. I'm doing a build thread on another forum, but hopefully I can get some local expertise, and maybe a few parts sources here.

What I've got is a 1987 Honda NSR250R (MC16) with a 1989 MC18 engine. I picked it up just 100 bucks in a pretty sorry state. The plan is to do a full rebuild with some modifications.

I'll summarise the build so far:

This is basically what I'm aiming for:
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And this is what I started with:

After pulling the engine:
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The engine was seized so I decided to investigate by pulling it apart. The pistons weren't seized but the crank was. Water had gone inside and rusted up the right hand bearing.
274985274982274983274984

[Wil_K]

Bottom cylinder was good
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Top cylinder wasn't. Looks like it was running lean, as there's detonation marks on top of cylinder and head.
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Heads are ok, but I've picked up another one in great condition to replace the top head that was slightly pitted.
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Calipers were seized up
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Down to the frame
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[Wil_K]

Split the cases to investigate. Looks like water had entered the crankcase through a lubrication hole near the bearing.
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After a good cleaning with de-greaser and a dremel:
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[Wil_K]

De-rusted tank and expansion chambers. I used steel BB's in the tank. Swished them around to remove any flakey rust, then a phosphoric acid soak for the rest. Yeah there's a few spots remaining. The chambers were done with a wire cup brush.

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Chambers painted:
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[Wil_K]

Calipers re-painted and rebuilt:
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Swingarm polished up to a satin finish. The frame is next and both will be clear coated.
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Forks rebuilt with new seals. Form bottoms painted and finished with a nice Showa decal.
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Polished up the triple clamp. Took ages as it was originally sand cast, and the casting marks had to be sanded down first.
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Loosely assembled the front end to see what it will look like.
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[Wil_K]

So right now I'm just getting it up to a rolling frame before I tackle the engine. Just need to do a bit more polishing and painting then I can get it assembled.

There's a fair bit more I haven't posted including lots of pics. It you want to see more of the build so far, check it out here: http://www.dotheton.com/forum/index.php?topic=39780.0

On another note, are there any NSR owners who have any spare parts available? I'm mainly after a crankshaft, in usable or rebuildable condition (my old one's not rebuildable). I'm also in need of a good barrel, re-plating them is hideously expensive ($575 quote from NZ cylinders, I think the only place that does it in NZ).

[ducatilover]

I'll be watching this, awesome little beasty :woohoo:

[Neal]

Hi there ,

if your crank pins are ok then you can get rods to rebuild the crank , there are some guys that can supply the main bearings but the centre crank seal is NLA if i am correct .

If you are not fussy , any nsr barrel with head can fit onto your casings .

[Kickaha]

I'm also in need of a good barrel, re-plating them is hideously expensive ($575 quote from NZ cylinders, I think the only place that does it in NZ).
Imdying had a place offshore that was considerably cheaper, think it's posted in one of the RS250 rebuild threads

[Sable]

Cool man. Bits hard to find?

[Wil_K]

Hi there ,

if your crank pins are ok then you can get rods to rebuild the crank , there are some guys that can supply the main bearings but the centre crank seal is NLA if i am correct .

If you are not fussy , any nsr barrel with head can fit onto your casings .

The old crank is pretty stuffed, there's pitting on the small end of the rods. Don't know the condition of the crank pins, but the rods were never made as a replacement part anyway so you can't get new ones (a guy in NZ has had custom ones made though). Bearings are somewhat hard to get, but this being a later model MC18, it uses the same bearings and seals as the MC21 and 28. Actually, an MC21 or 28 crank can be made to fit if you machine a few mm off the outside of the webs.

[Wil_K]

Cool man. Bits hard to find?

Yes very hard to find! Especially engine parts. It's a shame no one makes much aftermarket parts for these.

[gammaguy]

Yes very hard to find! Especially engine parts. It's a shame no one makes much aftermarket parts for these.

Not true

I have a warehouse in Japan full of parts for MC 11 16 18 21 28

[Neal]

You make a plan - if your pins are 24mm mc16 and early mc18 then you use rs125 rods .
If they are 25mm , you use the rods from Samarin ( Tucker ) or the crm125 with a yz small end bearing .

[Wil_K]

Not true

I have a warehouse in Japan full of parts for MC 11 16 18 21 28

Huh! Tell me more. Are there NOS parts? aftermarket? Do you sell parts?

[Wil_K]

You make a plan - if your pins are 24mm mc16 and early mc18 then you use rs125 rods .
If they are 25mm , you use the rods from Samarin ( Tucker ) or the crm125 with a yz small end bearing .

Interesting, I hadn't seen this info on nsr-world, which is where I've got most of my knowledge so far (I'm new to nsr's). Tucker - Yeah I've stumbled across his NSR blog and conrods.

[gammaguy]

Huh! Tell me more. Are there NOS parts? aftermarket? Do you sell parts?

Yes to all those questions

[imdying]

A 21 crank any good to you?

[Neal]

Interesting, I hadn't seen this info on nsr-world, which is where I've got most of my knowledge so far (I'm new to nsr's). Tucker - Yeah I've stumbled across his NSR blog and conrods.

They don't like to give out that kind of info because it is part of their business . They won't sell you crank bearings either .

[Wil_K]

A 21 crank any good to you?

Yes, I was thinking about just getting a 21 or 28 crank and modifying it to fit.

[SS90]

Yes, I was thinking about just getting a 21 or 28 crank and modifying it to fit.

I am unsure of the specifics of NSR cranks, but like has been said, there are plenty of options available round the place for rod kits (meaning rods, shims, big end bearing and crank pins).

Mr H is well known for not supplying rebuild kits for his 2 strokes, so experienced people have done the work for you there.
You seem really serious about the rebuild (opposed to a can of spray chrome and polished top yoke as many do), so a word to the wise is to rebuild your crank if at all possible, as if you fit another one, it is of unknown anything, and will likely bite you in the ass sooner rather than later (in any event, if you have to machine the webs to fit a later model one, it will need splitting anyway, and you 50% there at this point.

I appreciate you may be unable to do the crank yourself, but a competent machinist should be able to do a twin cylinder 2 stroke crank in about 2 hours (if they speciaise in certain models, dramatically less sometimes)

Ideally, the kits people use for early (pre 95) Honda RS125's would be suitable, (actually designed for 1988 till 2004 Honda CR125's as they are crazy cheap, easily available and a truly well known set up.

My opinion is that you may want to visit a helpful machine shop and take you crank to show them, if you cant find a bike specialist, I suggest someone that does Jetskis would be a good bet, as this boys are VERy experienced in crank rebuilds for high output 2 strokes.

Best of luck, oh and be careful what you read off the net too!

[Neal]

The problem with the old rs and cr rods is that the pins are 22mm and no use for the nsr cranks unless there is serious modifying done .
The pins on the nsr webs are all one piece .

[SS90]

The problem with the old rs and cr rods is that the pins are 22mm and no use for the nsr cranks unless there is serious modifying done .
The pins on the nsr webs are all one piece .

Same same with TZ250s, a shit set up I recon.

Whats stopping someone machining the webs to suit replaceable pins, I have machined several to suit larger pins over the years, is there the possibility of boring the cast pin out/off and machining a slug to suit (what I assume is a smaller pin for the CR/RS rods), meaning you now have a rod set up that can be rebuilt as and when it is needed?

[Neal]

The problem is on the rhs of the crank there is not enough metal around the pin and when a new hole is made for the pin it could split the web .
Rods are not the problem , there are 2 or 3 choices if you are willing to improvise etc , it's the seals that are problems for the early cranks .

[koba]

It's about know I'd be giving up and turning it into a bucket.
I know that sounds like shit stirring but it is seriously a good point in time to pull the plug if it looks like it's going to bleed you real bad.

[SS90]

The problem is on the rhs of the crank there is not enough metal around the pin and when a new hole is made for the pin it could split the web .
Rods are not the problem , there are 2 or 3 choices if you are willing to improvise etc , it's the seals that are problems for the early cranks .

What about simply machining the new pin smaller (on the ends where it meets the web, not where it runs on the bearing) to suit the existing web size......lots of early 2 strokes did this, (called a stepped pin) and an advantage of this is that they are easier to assemble, as the webs only press on the pin as far as the pin is machined to size, and if that's correct truing it up is way way faster than a conventional (unstepped) pin.

[SS90]

It's about know I'd be giving up and turning it into a bucket.
I know that sounds like shit stirring but it is seriously a good point in time to pull the plug if it looks like it's going to bleed you real bad.

It may be because I'm a thirty something, but writing off 250 jappa 2 strokes is a sin in my book, they are real collectors bikes now, and i think worthy of saving, just so long as you are aware it's for the love that you do it, not profit!

[Wil_K]

I'm certainly not writing this project off! Yeah it's going to be an expensive build, but at the end of it I'll have a like new NSR to enjoy for many years. As for the engine, the crank is really the hardest part to obtain/rebuild. Once thats sorted everything else is pretty easily obtainable.

Oh, and great discussion guys. Lots of good info to take onboard.

[Wil_K]

There's an NSR guy in south africa who was going to rebuild a crank for me. Unfortunately he didn't have enough usable parts to rebuild one in the end. However, he's working on a prototype crank that will accept replacement pins and different rods with a larger big end, so it will be completely rebuildable. Hopefully it works out well in his test bike.

[imdying]

It's about know I'd be giving up and turning it into a bucket.
I know that sounds like shit stirring but it is seriously a good point in time to pull the plug if it looks like it's going to bleed you real bad.It' only money and you can't take it with you. NSRWorld are idiots. Do you need an English workshop manual?

[Neal]

That guy is my mate , the frustrating thing here now is that it is very difficult finding someone that
A: will do the work needed
B : do it properly
C: do it when they say they will etc

I have some crank spares that i can donate to the project .
I was having a chat with our 2 stroke legend Neels and he says that the pins can last 4 rebuilds if looked after . I never asked if it was for race bikes or road bikes .


For me , i am going to be old with a gray beard and still ride my classic nsr at parade meetings when all the kids ask me why does my bike smell so nice :yes:

[Wil_K]

It' only money and you can't take it with you. NSRWorld are idiots. Do you need an English workshop manual?

I subcribed to nsr-world to get their online manual, I wasn't going to pay hundreds for paper copy! I know what you mean, they are idiots in some ways. I dont want to knock them too much though, they're still one of the best nsr resource someone like me has.

[Neal]

Tyga performance are your friends !

[imdying]

If you send it down with a rebuild kit, HPE can strip it, Coombes will balance it, and HPE will put it back together again. Won't be cheap, but it'll be better than it left the Honda factory (not hard it appears!). Phil has an MC21 one due, and a rebuild kit sorted out, so he'll probably get it done in a few months.

The NSRWorld subscription manual is a fucking have... it's missing the important stuff. Don't have the full one scanned into the computer yet, but they just upgraded the scanner/printer again from one monster to another, so it should autofeed it through in about an hour or so :D

[Wil_K]

Well if you do get that manual scanned in, I would love to get a copy.

Looks like I should start tracking down a set of bearings and seals. Neal, thanks for your offer of some crank spares, I may take you up on that. What have you got by the way? If you have crankshaft bits that are in good reusable condition, I'll be happy to buy them off you. And yeah Tyga is great. Haven't bought anything yet, but I will be throwing a few tyga goodies on to the bike, and I'll get a top end rebuild kit from them too.

[Deano]

It was a 1986 NSR 250R that changed my life .....simply awesome bike. Nuff said. Wish I had a late model 2 stroke in my stable...

[Neal]

I have a mc21 crank , mc18 r5 and r2 cranks and a mc16 crank . I was supposed to rebuild a crank but time flew past too quickly . The pins look good on the one crank that has been split . I want to build up a second motor for my 300 so will only use new rods and bearings .

The crank seals you get from Tyga , you modify the 21 seals to fit the old mc18 casings . I have bought seals from a bearing shop but have not tried them yet . I tried my luck with the outer main bearings and the guy says he can get me some when the main shop opens up again .
I have a 21 centre bearing with the seal and will show it to him and see if he can get it .
For the old mc18 crank with the big seal in the centre , the more people i ask the more say i can run a labyrinth seal so i will have one made up too .

Is your bike going to be a track bike or road bike or both ? I like the colour scheme .

[2T Institute]

Twin crank cost $100 to rebuild here (crank pins index properly and return with 0.00mm run out).................

Integral pin cranks are a real PITA , yes NSR world is full of fanboi's and not much else.

[imdying]

You can get a rebuild kit from rgvspares.com.au

[imdying]

It was a 1986 NSR 250R that changed my life .....simply awesome bike. Nuff said. Wish I had a late model 2 stroke in my stable...

86 was the NS250R? If so, incidentally, same here. I would buy one literally tomorrow if old Honda 2 stroke parts weren't such an overpriced pain in the arse.

[Deano]

86 was the NS250R? If so, incidentally, same here. I would buy one literally tomorrow if old Honda 2 stroke parts weren't such an overpriced pain in the arse.

Yeah thats the one. A guy imported a few bikes in a container around 1991 - I got it for $4K - it had 1500kms on the clock.

[Wil_K]

Neal, that's great. Would you be willing to part with your r5k crank? You aren't in NZ though I take it?

I was under the impression that the seals for the r5k would be the same as the 21 and 28. So again good info for me. And the bike will be a road bike, but with a minimal race bike look. Of course I'll also take it to the track for some fun!

[Neal]

Hi , not in NZ , I am moving to Perth in 2 weeks time and most of my stuff is boxed allready . The crank would need to be rebuilt as I would not trust it . Hopefully it has pieces that are ok . I will see what I can find for you .

[Wil_K]

Right, the project is back on track. I finished polishing the frame on Friday. It took a very long time! I'll probably apply some wax to the bare metal parts for protection, rather than clearcoat. It will be cheaper, and easier to touch up. Neal, I'm not ready to do the engine rebuild yet, but I'll keep in touch. It would be great if that crank you have is re-buildable, or if you have other usable crank bits. Let me know once you settle into your move what parts you can dig up.

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[Wil_K]

We have a roller. I've painted the wheels too. Just did them with some quality rattle cans. I didn't want to take the tyres off, so if the paint doesn't hold up, I'll get them done in 2K on the next tyre change. Also still hunting for some good used front discs before I break the bank buying new.

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[Neal]

Looking good , if you are not in a hurry for disc's , I have some buttons to convert to floating discs and you can have new outers laser cut .
If not , then have a look at Tyga , they have a stainless steel disc you may like .

[Wil_K]

Yes! just downloaded a free complete English service manual.

[Wil_K]

Currently in the process of assembling the rest of the bike, minus the engine. All the standard parts are going back on for now, until I get it re-vinned. Just trying out the tank and it appears to be too long for the frame. No wonder why it wasn't bolted on when I got it. A bit of investigation through the parts manual shows that it's actually an MC18 tank. Guess I'll just improvise a mounting solution until I build the custom sub-frame.

On another note, I ordered some discs from Oz. Almost $200 less than here after shipping!

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[koba]

Currently in the process of assembling the rest of the bike, minus the engine. All the standard parts are going back on for now, until I get it re-vinned. Just trying out the tank and it appears to be too long for the frame. No wonder why it wasn't bolted on when I got it. A bit of investigation through the parts manual shows that it's actually an MC18 tank. Guess I'll just improvise a mounting solution until I build the custom sub-frame.

On another note, I ordered some discs from Oz. Almost $200 less than here after shipping!

278087

Interesting.
Keep the updates coming!

[Wil_K]

Arrrg dammit!

Was removing a stuck stud when...
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There goes my only good cylinder. Ah well, this shit happens. Anyone got any barrels?

[Wil_K]

Brake discs arrived today.

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Installed, and the system bled. Just the rear sets to go, and we have a fully functional roller.

278320 278318

[koba]

Brake discs arrived today.

278319

Installed, and the system bled. Just the rear sets to go, and we have a fully functional roller.

278320 278318

What are the old ones like?

I need another for my bucket, doesn't have to be flash...

[Neal]

can that cylinder be welded and re taped ?

[Wil_K]

Old discs don't look good. They've got big u-shaped grooves worn into them.

http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1138.jpg
http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1135.jpg

[Wil_K]

can that cylinder be welded and re taped ?

Actually I think it would be possible. I'm gonna get it done and see how it turns out. May as well try, as the cylinder is scrap as it is anyway.

[koba]

Old discs don't look good. They've got big u-shaped grooves worn into them.

http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1138.jpg
http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1135.jpg

They all seem to do that.

How thin are they at the worst point?
Mine were looking 'not good' before the last 3 years of hard use, I'm thinking I should get some less rooted ones soon...

[Wil_K]

They look to be about 3.45 mm at the bottom of the groove. They're yours if you want em.

[Wil_K]

Cylinder repaired:

http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1812_zps92c4e108.jpg

[Neal]

:second: That's the way !

There is a mc16 on gumtree in aus , maybe they would sell the tank loose as the bike is stripped .

[koba]

Cylinder repaired:

http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1812_zps92c4e108.jpg

Looks professional, more info?

[Wil_K]

:second: That's the way !

There is a mc16 on gumtree in aus , maybe they would sell the tank loose as the bike is stripped .

I'll just stick with the MC18 one. It fits the lines of the frame perfectly, and mounting it won't be a problem when I build my custom subframe. I think it looks better too. There's actually plenty of NSR spares in NZ (not much good engine parts though), even an mc16 tank on trademe at the moment. I believe the NSR was pretty popular down here, but have become somewhat rare lately. I guess when the engine inevitably wears out, people just scrap them rather than go through the painful process of finding parts to rebuild.

Oh, another advantage of the MC18 tank is it has the bolt in surround for filler cap, the MC16 just has a one piece cap. This means I can use a number of aftermarket caps. I was planning on using a race style non-lockable cap.

[Wil_K]

Looks professional, more info?

Engine Rebuilders Auckland did the job for me. Welded, drilled, tapped, and resurfaced. Thought I'd give them a go as they're just down the road from my work. They did a good job apart from the thread is in slightly crooked, which it makes it slightly hard to slide the head on as the stud sits at a slight angle.

[Wil_K]

The Tyga Performance rear sets I ordered, arrived today. Spent the morning installing them and bleeding the rear brake system.

http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1821_zpsf877242d.jpg
http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1820_zps5c1aa601.jpg
http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1823_zps106689c3.jpg

[Neal]

Looking very good !

use some Loctite on the small " toe " parts of the gear change and brake pedal , mine vibrated loose once before .

[Wil_K]

Looking very good !

use some Loctite on the small " toe " parts of the gear change and brake pedal , mine vibrated loose once before .

Thanks for the tip Neal.

[Wil_K]

Stoked! I just scored a complete MC18 R5K + spare motor for a very good price. :2thumbsup

[Wil_K]

Here's what I got:

http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1940_zpsff555cda.jpg
http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1941_zps3a816a46.jpg
http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1943_zps49cbfb1c.jpg

Spare motor and other bits:
http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1942_zps0ab4d015.jpg

[Neal]

Oooo your hooked now !

[Wil_K]

It was an unfinished project, the guy spent 2800 on it apparently. Ended up giving up after his mechanic botched the engine reassembly and caused a crack in the transmission part of the case.

I've already split the cases on one motor. The crank feels good, he said it had new seals and some other work done but he couldn't remember exactly. All the gaskets and crankcase sealer look fresh, so there's definitely been some work done that's seen very little use.

I'm going to re-use that crank in my motor. I'll be tempted to replace the right side bearing though, as it's a bit noisy. Do you know a source for these Neal?

[Wil_K]

Actually the bearing is good, was just the bearing cage rattling a bit. The bearing was quite dry, I put a dab of oil in there and it now turns smoothly and silently. Is lubrication and issue for the primary side bearings? A guy told me they're usually the first to go. Turning the centre bearing, it feels like the centre seal is good too. I believe I will use this crank as it is.

[Neal]

I have looked for main bearings before and found some that will work except that they never had the pin in them . Until now I have not used a rebuilt crank only new or very good 2nd hand ones . Finding someone to do the work I wanted done to convert and modify pins was impossible in SA .
In a few months time I will start to play with cranks again . Deet is the only one in know on this side that can supply nsr bearings .
I use a syringe with some 2T oil to place a few droplets in key places when I bolt things up .

[Wil_K]

We have power...electrical power. Petrol power coming soon, pistons and gaskets will be ordered before the end of next week.

http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1967_zps6a3b410c.jpg

[Wil_K]

Mmm, shiney new top end parts, plus new crank outer seals as I discovered the old ones were actually the wrong size.

http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1969_zps7deeb375.jpg

[Wil_K]

Bottom end re-assembled:

http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1973_zpsa1c50236.jpg
http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1972_zps25d07137.jpg

[Wil_K]

And the top end:

Cylinders have been professionally honed. The top one looks almost brand new inside. The bottom one good, with some minor scoring. Power valves and exhaust ports have been de-carbonised.

http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1975_zpse1dd6c0a.jpg (http://s1253.photobucket.com/user/wil_nz/media/DSCN1975_zpse1dd6c0a.jpg.html)
http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1976_zps12aabafa.jpg (http://s1253.photobucket.com/user/wil_nz/media/DSCN1976_zps12aabafa.jpg.html)

[Wil_K]

Getting close to a runner. Engine now mounted.

http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1983_zpsadd86f8c.jpg (http://s1253.photobucket.com/user/wil_nz/media/DSCN1983_zpsadd86f8c.jpg.html)

[Moooools]

Getting close to a runner. Engine now mounted.

http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1983_zpsadd86f8c.jpg (http://s1253.photobucket.com/user/wil_nz/media/DSCN1983_zpsadd86f8c.jpg.html)

Shouldn't you be at the shop making wheels not leak?

[Wil_K]

Shouldn't you be at the shop making wheels not leak?

Cupcake?

While I was not helping out at the workshop, I got the rest of the bike together. And I'm pleased to say, it runs! :woohoo:

Plenty more to do though, such as:
- Leaking carbs to sort.
- Leaking thermostat hose.
- Setting up oil pump.
- Setting up RC valves.
- Carb tuning.

Not to mention all the modifications I have planned.

http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1985_zps6ffc1b2e.jpg (http://s1253.photobucket.com/user/wil_nz/media/DSCN1985_zps6ffc1b2e.jpg.html)
http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1987_zps45ae5413.jpg (http://s1253.photobucket.com/user/wil_nz/media/DSCN1987_zps45ae5413.jpg.html)
http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN1986_zps9e308ec3.jpg (http://s1253.photobucket.com/user/wil_nz/media/DSCN1986_zps9e308ec3.jpg.html)

[Neal]

Have you read Tuckers blog on his mc18 rebuild ? Looking good !

[Wil_K]

Have you read Tuckers blog on his mc18 rebuild ? Looking good !

Yep, I have read Tuckers blog, lots of good info on there.

[Wil_K]

New plan. So, before I get this thing set up and running sweet, I am going to swap the wiring loom to the MC18 one. I will also swap the flywheel, stator, and pickups for MC18 parts. I assume the MC16 items were left in the motor because the connections from those components to the loom are different between the 16 and 18. It will also mean I can use the PGM-II to run the RC valves and air correction circuit. At the moment I have the MC18 carbs on with the air correction circuit blocked off.

It makes a lot of sense to go this route. Currently the engine and electrics are a mix of 16 and 18 parts. I'm sure this will only complicate the tuning procedure, and also reduce performance.

[Neal]

The flywheel should have timing that is very close , there is a slight change of timing over the years . The only difference for the pickups is the connections on the loom .
The pgmii is better , even better if you can get a ignite can and plug it into the pgmii harness .
I batteled to get mine to work properly , I have since found out that there was a program error and has been sorted out .
I modified my flywheel to make it work . I don't have new dyno sheets but the improvement was better all the way up to where I had a splutter (now sorted) .

There is a mod that I have seen on the pgmii , my one had a switch installed where two wires were soldered inside it and extended outside the pgm , I flicked the switch on the dyno and saw 1.5 hp increase . I don't know how to modify it but it did work . Somewhere along the years of the bikes race life , the switch must has been flicked off by accident .

[Wil_K]

Got some aftermarket goodies. Expansion chambers and end cans, courtesy of KB member DEATH_INC., who gave them to me for free! Here's some pics of them installed. I will need to fashion new mounting brackets to attach the end of the stingers to the subframe, but otherwise they fit great. The obvious difference is they are a hell of a lot lighter than the stock pipes.

http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN2004_zps8ebd67a1.jpg (http://s1253.photobucket.com/user/wil_nz/media/DSCN2004_zps8ebd67a1.jpg.html)
http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN2002_zps82da4d39.jpg (http://s1253.photobucket.com/user/wil_nz/media/DSCN2002_zps82da4d39.jpg.html)

I've also installed the MC18 subframe, to make the installation of the 18 wiring loom easier.

I discovered something interesting connected to my PGM unit. Based on some research, it looks like an HRC derestrictor (has the HRC part code 'NKD'). Do you know anything about these Neal? Is this a derestrictor, and what do they actually do? The only info I could find was one topic on nsr-world showing something similar.

http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN2005_zps16f989b1.jpg (http://s1253.photobucket.com/user/wil_nz/media/DSCN2005_zps16f989b1.jpg.html)

[Wil_K]

Electrical conversion done, and aftermarket pipes fitted. Took it for a few laps down the road. Feels damn good to finally ride it! :2thumbsup Only took it up to 7.5k (out of 12 to 14k) revs to break in the new pistons and rings gently. Moves from low to mid range revs nice and smooth. It's quick too. No surprises there, but I was barely more than 1/4 throttle and well below the power band, but it was picking up speed nicely.

I'm still fine tuning the engine, and tidying things up. More pics and probably a video soon.

[imdying]

Don't rev it to 14.

[Neal]

Hi sorry for the delay , I am working in the bush ATM

The HRC derestrictor is a fancy wire splice . Just double check all your jetting before you blast off down the road .
What sort of sizes are you running ?
+1 on securing the silencers , they bounce around and crack the weld where the cone meets .
What is the plan with the pipes ? Black paint or clean and clear coat ?

[Wil_K]

I won't be blasting of anywhere without being sure the jetting is right. It's standard jetting at the moment. I'm on premix, but I will hook up the oil pump soon. Also, I'm thinking of putting the standard pipes on (for now). Mainly because: 1) It will make it easier to find a good baseline jetting setup, then I can make adjustments as I add modifications. 2) The aftermarket pipes could complicate the re-vinning process, as they are on the noisy side. They will definitely go back on though. 3) I would like to de-rust them. Not sure if I'll paint or clearcoat.

[al.ramsay]

Thought I should share one of my current projects. I'm doing a build thread on another forum, but hopefully I can get some local expertise, and maybe a few parts sources here.

I apologise for jumping into your thread, but just wanted to say Hi,
Ive been lurking around here for a while and following your thread as I am about to tackle a similar project over here in Perth.
Formally from Christchurch and in my late teens/early 20's had the pleasure of owning/riding many of the crazy strokers on the market - 20/25 years and about 30kgs ago!
I digress, I owned/rode/raced (all be it enthusiasm outweighed actual ability) had fun and broken bones to prove it a couple of TZR's, an NSR250 with what I was told at the time an RS motor, a bog stock NSR250R MC18 and lastly an NS400 that handled like a bag of bollocks, but went pretty well.
Ahh, Hindsight... if only I had kept 1 or 2 of them...



...Don't have the full one scanned into the computer yet, but they just upgraded the scanner/printer again from one monster to another, so it should autofeed it through in about an hour or so :D
+1 to an English Manual

Anyway, again sorry for the interruption, please keep up the good work, and I hope to pick your brains in the next while as soon as I get a chance to strip my '21.

[Neal]

Hi Al , keep us updated on your project and give a shout if you need help .


How's an update on the Elf special before i steal the colours for my next paint job !

[Wil_K]

I apologise for jumping into your thread, but just wanted to say Hi,
Ive been lurking around here for a while and following your thread as I am about to tackle a similar project over here in Perth.
Formally from Christchurch and in my late teens/early 20's had the pleasure of owning/riding many of the crazy strokers on the market - 20/25 years and about 30kgs ago!
I digress, I owned/rode/raced (all be it enthusiasm outweighed actual ability) had fun and broken bones to prove it a couple of TZR's, an NSR250 with what I was told at the time an RS motor, a bog stock NSR250R MC18 and lastly an NS400 that handled like a bag of bollocks, but went pretty well.
Ahh, Hindsight... if only I had kept 1 or 2 of them...



+1 to an English Manual

Anyway, again sorry for the interruption, please keep up the good work, and I hope to pick your brains in the next while as soon as I get a chance to strip my '21.

Hi, welcome to the forum. I hope you have fun with your NSR project. Feel free to ask questions, but I'm by no means an expert, this is my first NSR. There was an English service manual somewhere on this funny old site: http://www.dreamgate.ne.jp/NSR/index.html, but I can't seem to find it now. If you need one, send me a PM and I'll email you my pdf copy. The quality of the photographs are poor, but it's the only free translated copy that I know of. Or you could by an expensive one from NSR-world.

[Wil_K]

Right, an update:

The bike is currently in a shop getting re-vinned. I've been having issues with the left cylinder running very rich and oily. Not sure what is causing it, but it's really sapping the power and smoothness from the engine. When I get it all legal I can take it for a proper test ride, and try get a diagnosis. I'm thinking it may be the air correction circuit at fault.

As for the paint and bodywork, that will be a few months away yet. I've still got to find some sexier fairings. I'm still pretty keen to try get RS250 ones to fit.

Here's the bike as it stands now, rough MC16 fairings, MC18 tail and mismatched colours.

http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN2068_zps8dced20f.jpg (http://s1253.photobucket.com/user/wil_nz/media/DSCN2068_zps8dced20f.jpg.html)

[Wil_K]

Got this thing road legal! :woohoo: Almost a year to the day that I got it.

Been doing some photoshopping tonight. This is the bike with 1987 RS250 fairings and a 1992 RS250 tail. What do you think?
http://i1253.photobucket.com/albums/hh587/wil_nz/87-92_zpsbafd97ba.jpg (http://s1253.photobucket.com/user/wil_nz/media/87-92_zpsbafd97ba.jpg.html)

[imdying]

Is the float height correct on the LH carb? Needle and seat isn't weeping?

/edit: Don't like the tail, too much gap under the seat for the year. Need something more like MC16/18 bodywork.

[Vinz0r]

I quite like the RS fairing on it. That gap under the tail looks infinitely better than the blocky '87 tail piece.
But I always thought the pre 88 NSR plastics were ugly as sin, so that's probably biased my opinion a little.
(Also, I am not a purist, so don't mind frankensteined builds :D)

[imdying]

You just lack taste is all.

[Vinz0r]

You just lack taste is all.

I'ts a funny thing actually, the more you learn about a particular bike the more you come to appreciate it in it's standard manufactured form. When I was first looking to buy a bike I would see all of the shiny red Hyosungs around and marvel at how awesome they looked. Now that I have acquired a little more age and wisdom I scoff in disdain when I see one.
When I objectively consider how I would have looked at my current bike when I was an uninformed newbie it worries me slightly. I would have rather owned the shiny red 'sports bike'!!

I think this principle can be extrapolated to situations such as this in which the person with the more refined taste (you) disagrees with the person who prefers the more 'conventionally' aesthetically pleasing (or maybe just more modern looking) option.
If I had more experience with the older Honda 2 strokes I may just learn to appreciate the interesting lines of the MC16, but right now I just want it to look like a nice sleek MC21!
I can't appreciate it for what it is.

[Wil_K]

For your reference, this is an 87 RS250:
http://i1253.photobucket.com/albums/hh587/wil_nz/image_zpsde759789.jpg (http://s1253.photobucket.com/user/wil_nz/media/image_zpsde759789.jpg.html)

And here's an MC16 to compare:
http://i1253.photobucket.com/albums/hh587/wil_nz/87_red_nsr_zps7a374771.jpg (http://s1253.photobucket.com/user/wil_nz/media/87_red_nsr_zps7a374771.jpg.html)

I think it's a good looking bike (the RS), I even like the big ungainly tail, it seems to work with the rest of the bike. The bodywork on the 87 NSR on the other hand I'm still not a fan of. I just don't think it's aged well. The face is a bit too tall and flat, and their interpretation of the RS tail with all the road trimmings just doesn't quite do it for me. The later ones have more of a sleeker, lower, racier look. Basically, I want to make this look like an 80's racing bike with lights. My ELF graphics wont look right with MC16 fairings.

Oh, and now I sort of see where you're coming from on the tail I chose. It doesn't quite fit the period. Still looks OK I think.

[imdying]

It's just all the little design cues... the frame/forks/wheel styling etc, all screaming 80s, and that tail screaming 90s.

Doesn't matter a bit though, build what you like.

Loving all the little ducts on that RS250 though :yes:

[Neal]

I like the colour scheme , can you do a photoshop with the older style seat on it ?

[imdying]

I agree, great choice... that paint job will look awesome on anything :D

[actungbaby]

Right, an update:

The bike is currently in a shop getting re-vinned. I've been having issues with the left cylinder running very rich and oily. Not sure what is causing it, but it's really sapping the power and smoothness from the engine. When I get it all legal I can take it for a proper test ride, and try get a diagnosis. I'm thinking it may be the air correction circuit at fault.

As for the paint and bodywork, that will be a few months away yet. I've still got to find some sexier fairings. I'm still pretty keen to try get RS250 ones to fit.

Here's the bike as it stands now, rough MC16 fairings, MC18 tail and mismatched colours.

http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN2068_zps8dced20f.jpg (http://s1253.photobucket.com/user/wil_nz/media/DSCN2068_zps8dced20f.jpg.html)

pm if you want sell the fairings u have i have ns 250 with no body work ziltch not even around tail or pipes just wire mesh

[actungbaby]

Hi sorry for the delay , I am working in the bush ATM

The HRC derestrictor is a fancy wire splice . Just double check all your jetting before you blast off down the road .
What sort of sizes are you running ?
+1 on securing the silencers , they bounce around and crack the weld where the cone meets .
What is the plan with the pipes ? Black paint or clean and clear coat ?

Hi i just brought a honda ns 250 r 1986 its got wire mesh thing in the inlet port where carb goes

On is this restricter am new to 2 strokes ;-) Mines very rough though mostly complete

Just piston 56mm might be impossible to find . read where ns 400 can be used

But mean rebore barrell and replate of them too i assume .

anyways heres mine i looked at blue on trademe got this insteed fairings for my vfr 750.

pray i havent brought a dodo

[imdying]

Is there an English version of that post?

[speights_bud]

Can't remember if i posted in here a while ago or not.

Anyway, got a set of MC16 fairings here, (minus front guard). pretty good nick just need a paint where they've been sanded back a bit by previous owner.

$150 take em away. I can bring to manfeild next round of winter series or we can work something out.
Can probably chuck in the original moulded indicators for the front and maybe the wing mirrors if i can find them

Would prefer to see someone using them than collecting dust in the shed. That and I'll be a track official at the MotoGP in Phillip Island and need the $$ to buy the sign written "official" wet weather gear.

[Neal]

About the NS , what size gudgeon pin does it use ?
Start a new thread and maybe someone may have some answers to help .

[Wil_K]

Can't remember if i posted in here a while ago or not.

Anyway, got a set of MC16 fairings here, (minus front guard). pretty good nick just need a paint where they've been sanded back a bit by previous owner.

$150 take em away. I can bring to manfeild next round of winter series or we can work something out.
Can probably chuck in the original moulded indicators for the front and maybe the wing mirrors if i can find them

Would prefer to see someone using them than collecting dust in the shed. That and I'll be a track official at the MotoGP in Phillip Island and need the $$ to buy the sign written "official" wet weather gear.


That's a decent price for those fairings, but I'm still gonna move away from the original MC16 bodywork to some RS stuff.

[speights_bud]

cool as, i'm open to offers if anyone is keen

[Wil_K]

Small update. I think I have solved the problem of the plug fouling. I noticed that the upper cylinder was misfiring. The misfire was very bad at idle and low rpm, but would improve as the revs picked up. I initially thought electrical, so I tried swapping the coils, but this made no difference, and neither did a new plug. Battery is brand new and fully charged. I reset the idle screw to factory settings, and re-synced the carbs (visually) as I had been fiddling with these settings to try get things to improve. The changes made a small difference.

I figured it must be fueling so I pulled the carbs off again, a bit of an annoying job with the oil pump attached. Carb settings were as I left them, stock standard. Also, the air filter is brand new. I then checked the air correction circuit connections for blockages. No blockages, but I noticed something I had missed when installing the system. The 4 way connector has a small brass jet on the of the connections to restrict flow. I looked at the diagram in the manual and I believe I had the wrong hose attached to this connection. Swapped a couple of hoses around and put everything back together.
Huge improvement! The exhaust pulses now feel consistent out each muffler. And there is the same amount of smoke from each side too. Misfire is gone. Still, I only took it for a 5 minute ride. I'll see how it starts and runs tomorrow morning.

[imdying]

Successs :D :woohoo:

[Wil_K]

Successs :D :woohoo:

Not quite. I fixed the misfire, but it's still killing the top cylinder plug every time I start it. I'm thinking you could be right about the weeping float valve, I'll be replacing them. I also noticed the needles look quite worn, so I'll be replacing those too.

[Wil_K]

Picked up these carb rebuild kits from ebay. $26 US for both!

http://i1253.photobucket.com/albums/hh587/wil_nz/DSCN2189_zps41c5dd9e.jpg (http://s1253.photobucket.com/user/wil_nz/media/DSCN2189_zps41c5dd9e.jpg.html)

Replaced the needles, float valves, air screws and gaskets with the ones from the kit. Slow jets and emulsion tubes are different from OEM so I left the old ones in. I've also put in 140 mains to be on the safe side with the modified airbox lid and aftermarket pipes I'm running.

The bike now runs much worse! It won't run for more than a few seconds, and that's only on full choke. Only one cylinder seems to be firing (the problem cylinder). I'm guessing the needles which are not the same as the standard MC18 ones are now completely blocking the main jet at idle/low throttle, and my pilots are too small to supply enough fuel. Either that or I created an air leak somewhere when reassembling the carbs. I've ordered pilot jets in the next two sizes, so I'll see what happens when I fit those.

These motors are so damn sensitive!

[Neal]

On a stock motor you normally run 38 pilot jets and with some tuning sometimes a 40 . Compare the lengths of the needles , if you we're able to find adjustable needles in the past you needed the emulsion tubes to go with them as they were longer . I had a friend that used a shim to raise his needle .

[speights_bud]

Yep we use 0.5mm shims on the NSR to adjust the needles as we don't have the adjustable type. Sorry i cant help with Jet sizes as we are running the bigger carbs, chambers etc.

[Wil_K]

Ok, so I've put #42 pilots in, which seemed to make a small difference. I then screwed in the right hand airscrew almost completely and the bike will hold an idle and rev without choke. Things are still nowhere near right though. I managed to take it for a ride but there's just no power or torque anywhere especially down low. I did eye up the needles and they look the same length, I suspect they are probably a slightly different taper design to stock ones though. They look more like MC21 needles as the MC18 ones are brass. I'll do the shimming technique next and see what happens, and also measure the needles properly with a caliper.

[imdying]

If you have richened the pilot circuit up that much to make it run, perhaps it's not able to draw anything at all from the main circuit? Maybe a blockage? The emulsion tubes are all clean?

A friend has a whole heap of needles (HRC and OEM Honda), I think he has a spreadsheet of all the lengths and dimensions, if it interests you.

[Wil_K]

If you have richened the pilot circuit up that much to make it run, perhaps it's not able to draw anything at all from the main circuit? Maybe a blockage? The emulsion tubes are all clean?

A friend has a whole heap of needles (HRC and OEM Honda), I think he has a spreadsheet of all the lengths and dimensions, if it interests you.

Emulsion tubes and airways all seem very clean to me. I'm pretty sure the problem is the needles. I mean it was running rich on the old ones, and now it's the complete opposite. I would have bought OEM MC18 specific needles, but they are so hard to find and the one place selling them online was going to cost around $160 NZD shipped for a set.

That spreadsheet does sound like it could be useful. Does your friend also have some Mc18 OEM needles?

[Wil_K]

I pulled the needles out. The new ones are the same length as the old ones but they seem to be a larger diameter at the tip. New needles measure 1.35 mm at tip just before it tapers to a point, and the old ones 1.15 mm. Sure the old ones must be a bit worn, but I doubt they were 0.2mm larger when new.

[Drew]

If it was the needles, I would expect it to run fine once you picked the throttle up at all. Assuming that the were bottoming out in the jet because of the wrong taper on the tip.

If not run fine, at least idle on two pots.

Do you have another set of carbs?

[Wil_K]

Forgot to mention, I've got the bike running quite good now. I've got the standard needles in, and #42 pilots.

It sounds crisp and clean, and revs out nicely. The only problem is: no bottom end torque! I have to really slip the clutch a lot to get it moving. Even with the large pilots and air screws screwed in quite far, It is still a little lean down low. Ie. no low end torque, and difficult cold starting. Adding a touch of choke instantly brings back the bottom end torque confirming the leanness.

I decided to replace the rubber intake manifolds with a spare set, as the old ones had some cracking around where the boost bottles connect. It seemed to make a small improvement to bottom end torque and eliminated an odd flat spot at around 5k rpm. Still ain't right though.

I may try adding a light smear if liquid gasket to each side of the reed block gaskets just incase an air leak is present. Otherwise I'm lost as to why my bike requires such rich jetting. It seems the consensus is #42 pilots are about as big as you go on highly tuned NSR's and mine's only got aftermarket chambers, and a derestrictor. Or maybe this bike is an exception, and needs #45's?

[Neal]

I used 45's on my race bike with open carbs and premix , I would do a leak down test and check for any leaks sucking in air .

[al.ramsay]

Well, its been 5 and a half months since my last confession... ooops, sorry, wrong forum :wacko:

I finally got my hands on a MC21 that as reportedly working fine apart from a few bent/broken parts on the left hand side from a drop. When I got my hands on it, I stripped the fairings off as I didn't want the Repsol paint job (will get this stripped back and repainted) and started about finding out what needed doing. The bike wouldn't start due to the kickstart being locked up, so it was off to the doctor for diagnosis. Once the engine was completely stripped (parts then ordered) we discovered the crank was seized in one of the bearings. We are going to have a crack at replacing all the bearings (told by a motorbike engine builder that they can do the job) and got in contact with a crowd in the UK that can supply the bearings - certainly the koyo bearings listed for an mc18.

What I am actually leading to in this longwinded message is, is the bearings in the mc18 the same as the 21? if that is the case I can replace them. Otherwise, I will have to pull them out and see if there are numbers or something on them. If anyone has the bearing numbers, please yell out, just so I can check my information.

EDIT; Further to this message, I have found out that these can be sourced locally, well locally in Australia... thanks to Neal for pointing me in the right direction

Cheers

[gammaguy]

Well, its been 5 and a half months since my last confession... ooops, sorry, wrong forum :wacko:

I finally got my hands on a MC21 that as reportedly working fine apart from a few bent/broken parts on the left hand side from a drop. When I got my hands on it, I stripped the fairings off as I didn't want the Repsol paint job (will get this stripped back and repainted) and started about finding out what needed doing. The bike wouldn't start due to the kickstart being locked up, so it was off to the doctor for diagnosis. Once the engine was completely stripped (parts then ordered) we discovered the crank was seized in one of the bearings. We are going to have a crack at replacing all the bearings (told by a motorbike engine builder that they can do the job) and got in contact with a crowd in the UK that can supply the bearings - certainly the koyo bearings listed for an mc18.

What I am actually leading to in this longwinded message is, is the bearings in the mc18 the same as the 21? if that is the case I can replace them. Otherwise, I will have to pull them out and see if there are numbers or something on them.

If anyone has the bearing numbers, please yell out.

Cheers


I have parts manuals for all the NSR250,s let me know if you need the bearings decoded

[al.ramsay]

I have parts manuals for all the NSR250,s let me know if you need the bearings decoded

Do you have a parts list for the MC21 that you have in stock? I could be interested in buying some parts for future projects - certainly interested in pricing for a new crank if you have one?

I would like to know what the part number is for the big end bearings if possible? Wiseco B1059 bearings

Al

[gammaguy]

Do you have a parts list for the MC21 that you have in stock? I could be interested in buying some parts for future projects - certainly interested in pricing for a new crank if you have one?

I would like to know what the part number is for the big end bearings if possible? Wiseco B1059 bearings

Al

Got heaps of parts for them in Japan

Send me a list of your requirements also what part numbers you need

[al.ramsay]

Got heaps of parts for them in Japan

Send me a list of your requirements also what part numbers you need

My big one t the moment are the big end bearings for the conrods. I have the wiseco number but would help to have the Honda number if possible.

Do you have anything in terms of fairings? Decals to suit a '92? Complete lock set?

Cheers

Al

[Neal]

There is a guy selling cheap rod kits on ebay but I don't know anybody that has used them yet .
The big end bearing is the same as the crf150 . ProX sell them .

[Angreal]

Been following this thread since I went to the Isle of Man TT last year, stumbled across a stunning MC28 and decided that I needed another bike (previous one got stolen years ago). Picked up one from Japan, got it shipped here and gave it some TLC and just need new rotors to pass the brake declaration.

Anyway, keen to see your bike continue to progress :D Something about the smell of two strokes just seems right.

On a side note since it seems everyone who is knowledgeable about NSRs is here, I've been told that the cranks on the NSRs can't be rebuilt etc but it seems they can? Also, does the HRC RS250 crank swap into our bikes easily enough and does it offer anything? Sadly I have a lot to learn but I do know that I'm glad I picked up a tidy NSR while they still kinda exist

[Wil_K]

Feel free to hijack this thread while I procrastinate on the NSR project.

Angreal, the RS250 cranks will not drop in any of the NSR cases unfortunately. I think the RS conrods are a touch shorter as well. And yes cranks can be rebuilt. The biggest problem is the crank pins can't be replaced as they are a part of the webs. And OEM conrods were never made available. So whether a rebuild is possible will depend on the condition of your pins and rods. There is one place in Spain I think that does custom rods for the NSR though.



Anyway, keen to see your bike continue to progress :D Something about the smell of two strokes just seems right.


Saw a TDR250 take off from the lights a few days ago blowing a nice cloud of blue smoke. Got me exited to get back into the NSR soon.

[koba]

Saw a TDR250 take off from the lights a few days ago blowing a nice cloud of blue smoke. Got me exited to get back into the NSR soon.

Yum! :scooter:

[Neal]

Glad to hear about another nsr being revived !
The RS crank can fit into the older casings but not the mc21 or 28 , there is nothing to gain from the crank .
All the bearings can be replaced on the mc21/8 cranks and you have 2 options for rods , Samarin or unknown quality ones on ebay . I have not seen anyone use them yet .

Did that nsr race at the Isle of Man ?

[Angreal]

No. The only bikes that raced on the IOM TT were 600s, 1000s, 650 twins and electric bikes (oh and sidecars but those guys are proper crazy). It was one of the many bikes fans take to the island I was oogling over. Also saw a v4 desmo but it wasn't as nice in real life as I thought it would've been... I guess I just have my heart set on one day owning a NSR500 :shifty: The other bikes I quite liked there were all the old BSA bikes as they had a massive following but all the owners said the same thing which was along the lines of "rubbish bikes but we love them"

So I guess if my bike looks/runs decently it's one of those "it aint broke, don't touch it" moments then. Well a summer with a few decent rides and I've struck an oil leak and a fuel leak that I'll deal to over winter.

[Arronduke]

Just read the whole thread.
Keep working on this it is going to be cool when its done.

I had an 86 NS250R and loved it, it was the faring on the side stand that was soooooo cool.

Also enjoying the hours your putting in to getting the engine running right, long frustrating hours.
But in the end its worth the effort.

Will keep following this thread!

[Wil_K]

Cheers Arronduke. I love your RG, that would be a dream bike for me, though I think I'd prefer to have an RGV500 special!

I should really get back into this bike soon. It's just sitting in my Dads garage at the moment still ridable but I suspect something still isn't right with the engine. I've done a quick crankcase leakdown test which seems to suggest that either I have a massive centre seal leak or I just have air leaking across the read cages. If I test only one half of the engine I can't hold any crankcase pressure at all. But blocking off both sides and it seems to hold it's pressure ok. My sealing methods were a bit rough so I was expecting a few leaks. I'll take it into the workshop one day and fashion up a much better pressure testing jig.

Seems odd that there would be such a large leak since it idles very nicely. It is quite hard to start however.

I haven't given up on this, just procrastinating with a couple of other projects.

[koba]

I haven't given up on this, just procrastinating with a couple of other projects.

As we all do!

[Wil_K]

Probably going to have to sell the NSR :( If anyone is interested, make me an offer. Comes with lots of parts: wider MC18 front and rear wheels, MC18 swingarm, shock, front forks, brakes, radiator, new crank bearings and many other parts that I can't remember.

[Angreal]

Came back to check up on the progress and found you're selling it :weep: My bike is going very slowly and I ended up buying a Motocompo... I hope you decided to keep it and slowly continue chipping away at it though