Getting some helicoils done

[xwhatsit]

Allo,

Traced my oil leak down to an inability to properly tie down the valve cover because of some shot threads in the head. This wasn't a problem before, but I suspect there's some warpage that's gone on somewhere since the seize. I will try some silicone sealant first, but if it doesn't stop the clouds of smoke emanating from the mill, then I will get these helicoils done quicksmart (they should be done anyway).

Questions:

Where's the best (read cheapest, without being a waste of time) place to have some threads put into my aluminium head in Auckland?
I really really want to leave the head attached to the barrel (don't want to buy new gaskets, take out cam shaft, etc). Can I leave the head attached while they do the work?
Ballpark estimate of cost?


Thanks for the responses.

[hmmmnz]

basically you'll have to remove the cover as you have to drill a larger hole for the helicoil,
i would just do it yourself, its not that hard as long as your not the rip,shit and bust kinda guy,
you shouldnt have to replace the gasket unless it rips when you pull off the cover, really if its leaking you should spend the $20 to get another anyway,
the last helicoil set i bought cost me $50 and that came with all the bits to do the job(except the drill bit) and about 8 helicoils
if you were to get a shop to do it and providing they dont have to pull the engine out to gain access to the top of the head then you are probably looking at the $50 to $80 mark
have fun:Punk:

[xwhatsit]

Yay! Somebody replied!

I suppose I could do it myself -- although with me I must always remember I have a huge capacity to stuff up even the most simple things (like fitting a camshaft -.-'').

$50 doesn't seem too bad. When you say pull off the cover, you mean the valve cover, not the cylinder head? I'm not fussed about pulling off the cover, I was planning on doing that -- there's no gasket on the cover, so it's not a worry. What I don't want to do is pull off the cylinder head (where the threads are), as that means new head gasket, pull off camshaft (pain in the arse).

Thanks for the reply.

[hmmmnz]

where exactly is it leaking??
between the top of the head and the rocker cover,
or lower down, between the bottom end and the lower part of the head??
if its there then you'll have to pull the head, if its just the rocker/valve cover (top cover) then just that,
post a photo :D

i am guessing its a dohc engine and not some old skool push rod engine,
what bike :D

[hmmmnz]

<img src="http://i58.photobucket.com/albums/g257/hmmmnz/cb250Small.jpg">

[imdying]

The CB is the perfect bike to experiment with... give it a go yourself. The skills you'll pickup through practice here will be of use later :yes:

[boostin]

Im sure you could give it a go yourself, as long as you are handy with a drill and can keep it true when drilling out the old thread. Then its just a matter of tapping the new one, and screwing in the coil.

If you dont mind the road trip you can bring it over to us at Jennings Engineering. We are working from home over in Albany. Specifically cylinder head specialists, but also to alloy weilding, and other general engineering.

We stock and sell a range of helicoils and helicoil kits, give us a call if you want to talk about it.

Jennings Engineering 4159245

Thanks,

Paul

[xwhatsit]

where exactly is it leaking??
between the top of the head and the rocker cover,
or lower down, between the bottom end and the lower part of the head??
if its there then you'll have to pull the head, if its just the rocker/valve cover (top cover) then just that,
post a photo :D

i am guessing its a dohc engine and not some old skool push rod engine,
what bike :D

Hehehe, no pushrods here. Yep, it's leaking in the top arrow you pointed out, between the head and the rocker cover (I called it a valve cover, that's just what the Haynes says). So I'll just pull the rocker cover, nae sweat. Want to see what that camchain tensioner is up to after a few kms anyway.

@imdying: Yep, this bike has been quite the learning experience! Although sometimes I'd just prefer to be able to ride it instead of catching the bus, lol.

@boostin: I'll keep you guys in mind. Won't be attempting this until after next week, I'd say -- got to go to court :angry:. Jury service is ghey.

[xwhatsit]

<img src="http://i58.photobucket.com/albums/g257/hmmmnz/cb250Small.jpg">

That bottom arrow is actually between the barrel and the crankcase -- there was a tiny amount of leakage from there when I first got the bike. Found out why when I pulled the barrel when I did the rebuild, the base gasket was in about four pieces. Apparently a common problem with these engines -- perhaps why in the gasket set I ordered there were two base gaskets?

[vagrant]

The older XL's and Xr's used the same/similar engine, and mine leaked from the rocker cover. Turns out the frame flexes a little bit when landing jumps. The top engine mount is on the rocker cover, so landing a jump would pull on the rocker cover and cause a leak.
The solution was to either remove the top mount brackets completely, or to put a smaller bolt thru the holes, this would still give a clmaping efect to the mount, but with a bit more play in it.
They don't have a gasket in there because the head and rocker cover are machined as a set for the camshafts, and a gasket would stuff up the clearences.

[xwhatsit]

Wow! Would never've thought about the top engine steady causing problems. Not doing many jumps myself lol (apart from the massive pothole I hit in Northcote on Sunday which caused my glued-up speedo to become unglued once more). Really that top steady is just to stop sideways movement, not up and down, so the smaller bolt trick would do the goods.

I know the bearings are in the head and the rocker cover, and work together -- but why is this different from any other bike with a rocker cover gasket? Surely they're just machined to take care of the width of the gasket, like you do with a head gasket (that can't be out by much, either). Is it a side-effect of the plain-metal bearings which don't have shells? My next bike is going to have replaceable shell bearings everywhere :D

[vagrant]

Other bikes with rocker cover gaskets have a seperate clamp or plate to hold the cam(s) on top of the head. Honda "cheated" and used the rocker cover for two jobs. If you take the tacho drive off the side off the head, you can see your cam, and how they drilled and machined the bearing surface. As such it doesn't even have bearings in the normal sense of the word. It also means that they are a matched set, you can't get away with replacing one with out the other.:angry:

A gasket, even a thin one, relies on it being compressed to seal the gaps between two surfaces, and because it compresses, the running clearance between the cam and head can change. Too loose and the cam will rattle and bounce, destroying the bearing surface. Too tight and there is no room for oil, same result.:sick:

[xwhatsit]

Other bikes with rocker cover gaskets have a seperate clamp or plate to hold the cam(s) on top of the head. Honda "cheated" and used the rocker cover for two jobs. If you take the tacho drive off the side off the head, you can see your cam, and how they drilled and machined the bearing surface. As such it doesn't even have bearings in the normal sense of the word. It also means that they are a matched set, you can't get away with replacing one with out the other.:angry:

A gasket, even a thin one, relies on it being compressed to seal the gaps between two surfaces, and because it compresses, the running clearance between the cam and head can change. Too loose and the cam will rattle and bounce, destroying the bearing surface. Too tight and there is no room for oil, same result.:sick:

Well I'm probably in Mr Honda's bad books then, as I've replaced the head, used that with the original (?) rocker cover, then replaced the rocker cover :D The cam's not even from a CB250RS, lol.

My head bearings are not very beautiful, and with an unmatched bearing set I don't think my top end is going to be the most quiet, lol.

If it blows up again, I'm sticking a 500 single in it.

[xwhatsit]

Well, bought a helicoil (well, not really the actual Helicoil brand) kit off Enco in East Tamaki (sorry Boostin, would've gone to you but I was nearby at the time, and Albany is quite a commute). ~$56, included ten coils, tap and also the drill bit, which I was pleased about. Good guys there, helped me out even though I couldn't find the front door and wasn't sure exactly what size I needed (the looked at the bolt I gave them and confirmed it was a metric 6mm with 1mm pitch (?).

Again, enlisting the help of my uncle, worked out which bolts needed fixing, marked them off in the Haynes manual, and ended up dropping the engine out of the frame to get clearance for the drill (better than pulling off the cylinder head :D). A surprisingly simple process. What was very interesting, though, was that there were some threads that had already had coils put in, but had still stripped. I was worried that you can't coil a thread twice, but apparently you can -- pulled the existing coils out with some pliers, drilled (nothing much came out), then tapped (again, not much swarf). However the coils wound in fine and held perfectly when the bolts went in.

Of some worry was the fact that two of the threads, which are supposed to be oil sealed with a washer, were inaccessible because they went so deep. Unfortunately they had to be left as is, however we put some sticky shit on the threads and the heads of the bolts in an effort to keep them sealed.

How many threads? Well out of a packet of ten, there are two coils left :D. Hopefully that will keep the rocker cover watertight now. Haven't fired it up -- waiting for said sticky shit to dry, and need to do all the boring stuff like tanks and seats and plug the electrics back together.

Thanks for all the help, it's much appreciated.

[xwhatsit]

Well I'm quite pissed off. After a trouble free day (yesterday), with not so much as a speck of oil, I wake up early so I can ride to Piha on my way to work (quite the detour, lol). First of all, although the bike starts (in normal bump-start fashion), there is absolutely no electrics. No horn, no dash lights, no indicators, nothing. Plenty of battery. So I kill the engine, dismantle almost all of the electrics, and then inexplicably they start working again. No idea.

Next thing I discover as I pull over to the side of the road just before Titirangi, is three Triumph (classic Triumph) riders, one who says he needs a trailer. I don't make much sense when I talk to them, as I'm on such a high from the twisties so far, but they laugh when I bump start the bike down the hill, but sadly also point out my bike is leaking oil and smoking :angry:.

It looks like it's coming out of those two un-helicoiled threads. Seems that the sticky shit only held up for so long, but not a high-rpm blat out to Piha (I really need another gear, or to fool around with sprockets). What are my options here? The reason those holes weren't coiled was that the thread went extraordinarly deep into the cylinder head, and there was no way you could get the drill and tap in there. One thing my uncle mentioned was that you could almost just put a coil in at the top (there's plenty of meat, I think) and use a shorter bolt.

Thanks again guys. Mum reckons my bike is getting jealous from the attention I give my girlfriend and she wants me to take her to pieces again and again. I'm glad my real girlfriend isn't this needy.

[xwhatsit]

Here's a picture, too.

Is the idea of putting shorter bolts in and a thread at the top drastically dangerous and very silly? It seems the smartest way to do it, to me. I'm sure I've got enough bolts lying around to find some the right length.

[Ixion]

Hm. Those are the bolts that clam down the camshaft bearing surfaces. Quite important. I'm looking at those holes and wondering if there are supposed to be dowels in there, would explain why the threads start so far down ?

[xwhatsit]

By dowels do you mean like threaded rod stuff and then I wind a nut on top the of the rocker cover? Because in the Haynes manual they're just normal bolts, except with copper washers.

[Ixion]

No , I mean like little short tubes of hardened steel. They fit into the wider top bit above the trheads, and stick up above the surface. Then when you fit the cover the dowels fit into similar slightly oversize holes in the cover, so that it is precisely located. The bolts go through the dowels.

Usually if a cover incorporates any sort of bearing surface it will be dowelled so that it is precisely located.

[xwhatsit]

As far as I can work out there are none, although there are at least three other dowels which have larger holes in the head and rocker cover to accomodate them. There's also like a little pin that aligns with the little indentation next to the right exhaust valve. That picture shows no dowels because it's from an old pic, but they are all fitted.

Haynes shows no dowels in any of the exploded diagrams.

Because of the importance of these bolts, it is therefore unwise to faff around by putting in shorter bolts? In that case, how is it possible to put in coils so deep? Can you get extender-thingies for drills?

[Ixion]

You can get extra long drill bits. But what worries me is why it's like that.

Engineers don't (usually) do things without a reason. So those threads were buried deep for some good reason. It would have been easier machining to put the threads at the top of the holes like the rest. So the design engineers thought that there was a reason that justified the extra machining work. I don't like changing things until I've worked out WHY it is the way it is.

Um. Another thought. Is that how the oil gets to the cam bearing surfaces ? Look VERY closely at the holes - are they cross drilled at all. How DOES oil get fed to that plain bearing? I've seen that before, an oversize hole with a cross drilled oil way. In which case you definately would NOT want to screw a close fit bolt into the top bit of thread, thus blocking of the oil supply? Very quick seizure.

EDIT: Incidentally that would explain the difficulty of getting an oil tight seal, because that part of the joint would be exposed to pressure fed oil, not just mist and splash like the rest of the joint.

[xwhatsit]

I think you might be right there, Mr Ixion. Would explain why those bolts (and one other) are supposed to have copper washers when no other ones do.

That said, there is the oil reservoir in the middle, where the cam lobes go. The lubrication diagram in the Haynes manual only shows oil going to the oil reservoir in the middle, up through the hole underneath. And by looking on the old head, I can't see any passages in those threads, and when I tried to blow on them with my lips they sure seemed to be airtight.

Obviously if I can get extra long drill bits, I can get extra long taps. You're right, of course, it's better to do it the way God (aka Mr Honda wot designed my engine) intended.

EDIT: Just went out to garage with a bit of wire, and checked the depth. Looks like the supplied drill and tap will reach, but there's just less than 1cm left of the cutting part of the drill and the shaft of the tap left. Maybe I should try drilling and tapping the spare head on my own, to see if it can be done, except not put the coils in of course.
EDITY EDIT: Actually no, the tap won't reach because the shaft is too fat for the hole.

[Ixion]

How deep do the original threads go ? I've gotten away in the past with using a longer bolt. The top of the trhead is stripped but often the hole is tapped deeper than the bolt reaches , so if you use a slightly longer bolt it can reach undamaged thread. Have you tried screwing the bolts in without the cover, to see if there is more thread?

[xwhatsit]

Very interesting idea, that! Will try with the spare rocker cover/head to see how deep the bolt reaches normally, and if there's more room. However the aluminium is like chocolate, so not sure how permanent it would be. Would be wonderful if somebody has a set of super-long taps that I could borrow for a few hours, but I won't hold my breath.

Cheers for the advice.

EDIT: Looks like I've got 5-6mm of thread left to play with. Shall ring up ENCO tomorrow and ask if they've got some longer taps before I try that, though (looks like they're called `long shank taps', can't see any on their website but will ask anyway). Would rather do it more permanently. The smell of burning oil (four-stroke, that is) is really playing on my nerves :)

[Ixion]

They're called pulley taps, but they are rare, I've never seen one in the metal. I'm also not sure if the "outer" thread of the helicoil is a standard metric thread or not.

[xwhatsit]

Ooh ok, doesn't sound promising. It's probably not only the outer diameter, but the depth of the `teeth' (don't know proper term there) as well.

Oh well I'll ask them anyway. Surely people must come into these sort of problems all the time.

Could I get my existing tap remachined? Have a lathe cut down some of the shaft where the drill grips? Certainly don't need the entire length of that, not even close. Although I bet that's bloody hard steel.

[xwhatsit]

Alright, no cigar at Enco.

Is the tap too hard to have part of the shaft lathed down in diameter? If not, where's the normal sort of place to have something like this done? Shouldn't be very expensive, should it?

[Ixion]

Too hard to turn I would think. It would have to be ground. If it's not a lot to come off you could do it by hand just with a bench grinder, the shank doesn't have to be perfectly round.

But some taps have the shank smaller than the teeth - some have it bigger, it's a maker by maker thing. Might be worth asking to see a few brands, on the off chance.

[Madness]

Helicoil Taps are specific only to the inserts, standard taps intended for what would be the internal thread of the coil match but the outer thread is oversized and a long series Helicoil tap would be ex overseas.

In Welly here there is a business called PG2000, they are specialist Grinders and would probably charge $50 or so to reduce the shank diameter. There's probably someone like them in Auckland, Tervor Lindsay comes to mind (Linbide Tools).

If it were me I'd be talking to this (http://www.kiwibiker.co.nz/forums/showpost.php?p=960337&postcount=7) guy.

Edit:/ No offence Ixion.

[Ixion]

None taken. I questioned earlier whether they were a standard thread .

[xwhatsit]

@Ixion, aye, I thought the steel would be bloody hard if it's a tap. Cutting a cutting thing shouldn't be easy :). Yeah, there's not too much to be taken off, and it's only so it'll fit down the hole, so it doesn't need to be very exact. I keep reading about this ISO standard for taps; apparently the shank size is stipulated somewhere, and for a tap which looks about M8 (for a M6 coil), the shank will mostly be bigger.

@MAXIMUSDEMERITUS, yep, the kit is actually a brand called `Recoil'. I read up on their website, and they said they have custom tap sizes. Will look up that name, Linbide tools. Thanks for that. Yeah! Should call boostin up! Completely forgot. Will call as soon as I have some spare time (sure as hell not tomorrow).

Thanks all!

[xwhatsit]

Woohoo! Tried a whole bunch of places, some people sounded a bit scared about tooling a tool (`why not just get a longer tap?'), then somebody said `we don't normally do stuff like that, but try Alpha Engineering -- that's where we send our jobs'. Tried them, got a hands-on guy straight away, told me that he could do it, he'd hold it in the lathe while he ground it down. I asked him to forgive me because I'm a university student, so I need to know the price first so I know I can actually pay him once the job is done, and he ummed and ahhed in an ominous manner until he said `well it's a fiddly job, so probably around about $35 I'm afraid'. Woot!

So tomorrow I'm off to bloody Manukau City (no offence to those that live there, but I hate riding around that place! Traffic lights and 3-4 lane roads and trucks for Africa!).

Yay for hands-on people. Wish I were one.

[imdying]

You could buy a bench grinder for that price, it'd make short work of the shank :yes:

[Warr]

Woohoo! Tried a whole bunch of places, some people sounded a bit scared about tooling a tool (`why not just get a longer tap?'), then somebody said `we don't normally do stuff like that, but try Alpha Engineering -- that's where we send our jobs'. Tried them, got a hands-on guy straight away, told me that he could do it, he'd hold it in the lathe while he ground it down. I asked him to forgive me because I'm a university student, so I need to know the price first so I know I can actually pay him once the job is done, and he ummed and ahhed in an ominous manner until he said `well it's a fiddly job, so probably around about $35 I'm afraid'. Woot!

So tomorrow I'm off to bloody Manukau City (no offence to those that live there, but I hate riding around that place! Traffic lights and 3-4 lane roads and trucks for Africa!).

Yay for hands-on people. Wish I were one.

Sounds good.. Could be a good idea to add the Phone number for Alpha and the name of the guy for anyone else wanting fiddly jobs of an enginnering nature done :)

[xwhatsit]

You could buy a bench grinder for that price, it'd make short work of the shank :yes:

Hahah, but I couldn't trust myself not to cock it up. They're that cheap?! Next tool I'm buying though is a torque wrench, so I don't have to keep borrowing my Uncle's (after seeing the amount of stripped threads on this bike, I've turned into a torque wrench Nazi; I'll use it on any thing I can).

@Warr: He's in the Yellow Pages; will post up here his details depending on if it's a good job or not tomorrow, lol.

[xwhatsit]

Well I got it back. Beautiful job; don't know what he did (he tried explaining something to me, but they were all such long words I forgot). You can't tell that it wasn't just made like that. Cost me $30 all up. Now all that remains is for me to do the coils, I suppose. Not looking forward to that. Might have to wait until after the girlfriend's 20th on Sunday, as I have to drop the motor out of the frame.

I highly recommend these guys on the basis of that job. Friendly staff, very precise job (I didn't need anywhere near that amount of precision), and a very cheap price.

Alpha Engineering, 5 Mana Place (off Wiri Station Rd), Manukau.
(09) 262 3013 mail@alphaengineering.co.nz

[Madness]

Good stuff!

Now remember, there is always time for lubricant... on the Tap of course.

I know a guy that used to work on Trawlers, he told me once he had to torque down some engine bolts on a Korean boat. Apparently he was unsure how much to tighten them nd when he asked the crew he was shown 5 fingers. Hmmm, 5. I wonder if that's 500ft/lb, seems a lot. it turns out that the specification was in fact a long bar, with 5 fishermen jumping up & down on the end!!

[xwhatsit]

Good stuff!

Now remember, there is always time for lubricant... on the Tap of course.

I know a guy that used to work on Trawlers, he told me once he had to torque down some engine bolts on a Korean boat. Apparently he was unsure how much to tighten them nd when he asked the crew he was shown 5 fingers. Hmmm, 5. I wonder if that's 500ft/lb, seems a lot. it turns out that the specification was in fact a long bar, with 5 fishermen jumping up & down on the end!!

Cheers, I'll remember to lube it up, but with the amount of oil springing out from that bolt, who would've thought I'd ever need more lube? :D

Hahaha, they must be the bastards that put my engine back together before I bought it!

[xwhatsit]

Well I dropped the engine out the frame (man that's hard to do by yourself -- ended up laying the bike on its side), pulled off the valve cover, grew some balls and helicoiled those last two holes all by myself. I practised a few times on the old cracked head I've got until I got more confident. Man those are deep holes! It took me ages to get the tap all the way down, as instead of using an electric drill I used a 7mm spanner (camshaft sprocket in the way).

Used some blue Loctite stuff. Seems much better than that other flaky black stuff.

As I was pulling it apart, one of the other bolts that had been coiled earlier didn't want to come out. When I lifted off the valve cover, I saw why -- the coil had come out with the bolt. No matter, I thought, I'll just screw the coil back in (I reused that one, as I had only two coils left for two holes to do). Anyway, I just about cried when I put the thing back together; the bolt just kept turning :sick: :bye: Well I'm hoping this time that because it's in a different place, oil will not want to come shooting out of it. I liberally smeared the blue shit all over the top of the bolt as well. If this doesn't make it oil-tight I am going to bawl. It'd better stop smoking, as tomorrow is the last day my WOF is valid, so I have to get that done.

Leaving it overnight for the silicone to cure now. Will drain the oil out tomorrow to get rid of the inevitable swarf (I don't totally believe the vacuum cleaner got everything) in the sump, then put in some new stuff for a very short time like I did when I rebuilt the engine.

[Madness]

Will drain the oil out tomorrow to get rid of the inevitable swarf (I don't totally believe the vacuum cleaner got everything) in the sump, then put in some new stuff for a very short time like I did when I rebuilt the engine.

Excellent, I was worried you'd overlook the swarf issue. be sure to change the oil filter when you replace the "flushing" oil.

Ten points.

[xwhatsit]

Excellent, I was worried you'd overlook the swarf issue. be sure to change the oil filter when you replace the "flushing" oil.

Ten points.

Oil filter? What oil filter :D

No such thing on this engine from Honda's engineering brilliance... :lol:

Yep, thanks to KB, I'm now of the firm opinion that although Delo 400 oil costs $35 a bottle, it's still cheap compared to what happens if I leave it alone. Especially important on a bike like this without a proper oil filter (just some steel mesh designed to catch metal chunks the size of M6 nuts).

[Dodgyiti]

Oil filter? What oil filter

Yeah, crazy eh?

Have a look on the interweb- someone will have plumbed something in. I did it on an old Suzuki. I used braided hoses and a chrome capsule thing that had a reusable foamie element type thing inside and threaded outlets either end. Ended up looking not too out of place, and it took another 200mls of oil to fill the capsule and lines, and that can't be a bad thing.
This was a long time ago so I have no idea what is avaliable now.

[xwhatsit]

Yeah I've seen pictures of a CB250RS with an oil cooler added. Should be possible to do that with an in-line oil filter too.

If the bike does leak oil out of that new fucked thread, what can I do? It's already been helicoiled once. What happened was when I undid the bolt, the coil came out with it. If the thread that the coil screws into is stuffed, what are my options here? Bigger thread?

In searching around the internet for answers to that question, I stumbled across this page: http://www.thumperpage.com/articles/nftfoh.html I know exactly how this guy feels :lol:. Actually from his description of the engine, it sounds almost identical to mine. Just twice the capacity. Probably the XL500 motor.

[Ixion]

Try Loctite stud lock (best to use the high temperature version ) on the OUTSIDE of the helicoil thread. Stud lock is high strength . If the thread is totally buggered it may not work, but if there is anything left it may hold the helicoil enough to tighten the actual stud. DON'T let the StudLoc get onto the bolt-helicoil joint or you'll never get the bolt out. StudLoc is NOT designed ever to be removed.

[xwhatsit]

Try Loctite stud lock (best to use the high temperature version ) on the OUTSIDE of the helicoil thread. Stud lock is high strength . If the thread is totally buggered it may not work, but if there is anything left it may hold the helicoil enough to tighten the actual stud. DON'T let the StudLoc get onto the bolt-helicoil joint or you'll never get the bolt out. StudLoc is NOT designed ever to be removed.

Ahhhh.... ok. Cheers! Hopefully it'll all the oil will stay inside the engine at least for the WOF though.

[terbang]

I've kept a few old jappers running way past their use by date so therefore I have had helicoil a lot of threads recently. The trick is to closely inspect all threads and recoil anything that looks even slightly dodgey. For a M6x1 thread they recommend drilling a 6.3 mm hole before tapping. This is probably fine for a steel casting but for an aluminium casting using a hand drill I find that a 6mm drill is better. Keep a steady and accurate hand when drilling and use plenty of lubricant when cutting the thread. I have great success with this producing a stronger and more durable thread than original.

[xwhatsit]

Woooo! Engine has stopped pissing out oil and smoke off the headers has largely vanished. There still seems to be a very small element of smoke misting off the headers, I think it's probably just residual shit that will burn off.

So that means I can get a WOF; went to VTNZ place and waited for the fat indian guy to finish his lunch, then he failed me for the following things: too much movement in brake pedal (it's comfortable there, I like it); headlight is wrong spec (bullshit! I looked at the lens and it is exactly the correct NZ spec); and the best one, my footpegs move around too much. What?!?!?! He said the hinge they fold up on is not tight enough. What a load of shit. If they were any tighter, they wouldn't fold. Not like they can come out anyway, there's a bloody split pin through the end.

So I went home, ranted and raved, then rode out to a tiny little garage that I'm not telling you where, but PoshTourer's mate (who sold me the spare CB250RS -- the frame I just sold to a racer who's putting an XR500 lump in it) told me he gets his WOFs for. Result? No bullshit, he actually looked at stuff that matters (like wheel bearings, brakes, brake fluid), and gave me a pass. I know my bike isn't perfectly up to scratch, there's plenty of areas I need to fix, but footpegs with hinges that are too floppy? Faaaark.

Anyway, I'm happy now.

[psyguy]

If the thread that the coil screws into is stuffed, what are my options here? Bigger thread?

In searching around the internet for answers to that question, I stumbled across this page: http://www.thumperpage.com/articles/nftfoh.html I know exactly how this guy feels :lol:. Actually from his description of the engine, it sounds almost identical to mine. Just twice the capacity. Probably the XL500 motor.

oh mate, i can confidently say that i'm doing so much better in my rebuild than this poor guy... :no:
but would be a hell of a laugh spending some time with him fixing things up in his garage i imagine :rofl:

[xwhatsit]

oh mate, i can confidently say that i'm doing so much better in my rebuild than this poor guy... :no:
but would be a hell of a laugh spending some time with him fixing things up in his garage i imagine :rofl:

Hahaha yes. I've been following your thread with some interest -- it seems you've got a good engine there. Hope the rebuild continues to progress well, it's going to look stunning I think.



I think there's an oil seal on a hollow dowel thing in the join from the barrel to the cylinder head that is leaking a little. There is a very small amount of oil on the outside of the barrel, just under the head gasket. Also, there was some white smoke when I first started the bike up today. This went away after a while, and didn't reappear when I started the bike the three times after that today. If the cylinder head gasket was blown, I think the effects would be much more noticeable.

Oh well, we'll see. If the worst comes to the worst, I'll get an XL/XR500 lump and (as the man who bought the rolling frame said) chisel off the `500cm^3' and engine number and replace it with my engine number and `248cm^3'. Problem solved :D

[Ixion]

White smoke after standing, clearing and not reappearing is usually oil seeping down valve stems and past the valve seals (if there are any). It may be due to worn valve stems, worn guides and or worn seals. Or, some engines just do it. Especially older designs. Ask Mr Motu about his diamante sometime.

Not a biggy on an old bike, just keep the oil topped up.

[xwhatsit]

White smoke after standing, clearing and not reappearing is usually oil seeping down valve stems and past the valve seals (if there are any). It may be due to worn valve stems, worn guides and or worn seals. Or, some engines just do it. Especially older designs. Ask Mr Motu about his diamante sometime.

Not a biggy on an old bike, just keep the oil topped up.

Ooooh ok. I replaced the stem seals when I put the top end back together last, but there's other things than that on your list.

Well I won't lose too much sleep over it.

Next thing to play with is the carb. I have two carbs, and a carb rebuild kit. Ought to be able to get this one right at least.

All I can say is that I'm glad I don't own a Triumph. Oil leaks aren't much fun.

[psyguy]

Next thing to play with is the carb. I have two carbs, and a carb rebuild kit. Ought to be able to get this one right at least.


yeah, carbs are the next thing for me too (once i get the engine out of the way that is). i look forward to seeing how you go with it. cheers