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TheRealWolf
20th August 2012, 03:54
Hi there,
Im posting my rebuilding of a Suzuki GN250 to a kind of cafe racer. I Am from the south of Germany and our TÜV, somthing like your WOF is vry restriktive so lots of modding is not allowed.
I have startet with a bike like this:

http://www.motorcyclespecs.co.za/Gallery%20%20A/Suzuki%20GN%20250%2082.jpg

and I ended with this:

http://www.repage8.de/memberdata/keep-it-kiwi/GN250Maori14.jpg
http://www.repage8.de/memberdata/keep-it-kiwi/GN250Maori15.jpg
http://www.repage8.de/memberdata/keep-it-kiwi/GN250Maori16.jpg

only the seat I want to change in a nice cafe racer style but first I have a ride to the Tüv to get my licence.
Greatings from the real Wolf from Germany

Paul in NZ
20th August 2012, 09:07
Good effort so far though.....

ducatilover
24th August 2012, 00:00
:Punk: Love it, keep up the good work!

Matariki
2nd September 2012, 01:58
Very nice!
How much has it cost you so far to get it to its current stage?
Did you do the paint job yourself?

TheRealWolf
14th September 2012, 03:35
Hello,
the costs until now are not very high, parts to pay are the handlebar, the turn signals, the air filter, the rear light, I think all in all about 150 Euro, about 300 NZDollar. The paint job is only the black colour, the race strip is a decal, also the red lines.

http://www.repage8.de/memberdata/keep-it-kiwi/GN250BodenseeSW.jpg

http://www.repage8.de/memberdata/keep-it-kiwi/GN250Bodensee02.jpg

http://www.repage8.de/memberdata/keep-it-kiwi/GN250Bodensee01.jpg

Now I try to tune the careburator to the new air filter. I need a bigger jet. With a rear sprocket wheel with 16 sprockets the GN is now a little it faster. I need a chain wheel with 37 sprockets for a little bit more topspeed, I hope i can reach the 140 km/h. At the moment I reach 130 km/h at 7900 rpm.
Maybe I try the 300ccm Cylinder which you can get via e-bay. Here in Germany som people are very happy with it.
Greetings from the real Wolf...

ducatilover
14th September 2012, 09:08
:Punk:
The 300cc kit works okay, it's a noticeable difference
Mine destroyed the clutch with the 300cc motor :laugh:

TheRealWolf
22nd September 2012, 23:25
Hello,
a little update while I'm working on my bike: I raised the rear end of the tank about 6 cm to get it paralell to the frame. Now i have to raise the seat at the front end for a little so the line goes straigt from front to end.

http://www.repage8.de/memberdata/keep-it-kiwi/GN250MaoriTanklinie.jpg

Greetings from beginning autumn at lake constanze, Wolf

Smarsh
9th October 2012, 11:27
hey mate, bike looks great. was just wondering how exactly you went about lifitng the tank to get it paralell to the frame?

ducatilover
9th October 2012, 13:13
hey mate, bike looks great. was just wondering how exactly you went about lifitng the tank to get it paralell to the frame?
Put a spacer under the rear mount with longer bolts, same as I've done.
You can also modify the front rubbers to bring the front down too

Smarsh
31st October 2012, 16:20
Put a spacer under the rear mount with longer bolts, same as I've done.
You can also modify the front rubbers to bring the front down too

Hey, thanks for the reply. I had a look, did you have to bends the rear tank flange, or elongate the holes, because as I lifted the tank, the holes in the tank and the threaded holes werent on the right angle. Also do you know anything about modifying the seat so its more in line with the tank, so the bike doesnt look like its folded in half?
Cheers

ducatilover
31st October 2012, 20:11
Hey, thanks for the reply. I had a look, did you have to bends the rear tank flange, or elongate the holes, because as I lifted the tank, the holes in the tank and the threaded holes werent on the right angle. Also do you know anything about modifying the seat so its more in line with the tank, so the bike doesnt look like its folded in half?
Cheers

The holes in the rear of the tank should have spacers or washers in them, take them out and the holes end up being about 15mm round. Then you can put the tank on any angle you want :D

I removed the seat cover and trimmed the foam and seat base (you can see it in my signature pic) then re-fitted the seat fabric. Fairly easy to do

aimee
1st November 2012, 10:10
Gorgeous. Just gorgeous. You've taken a bike that started out being pretty cute, and made it even cuter :)

/ponders doing something similar with hers (I have a GN125)

TheRealWolf
17th November 2012, 18:36
Hello,
sorry my replay comes so late, I had trouble with our Internet. As was said I put spacer under the rubber Part that is at the rear end of the tank. I had to change the front mount of the seat to fix it. Because of the cold weather here I cant take a Picture, but whe the weather is better yuo get it.

Foggy autumn:
http://www.repage8.de/memberdata/keep-it-kiwi/121116GNImNebel.jpg

first day winter:
http://www.repage8.de/memberdata/keep-it-kiwi/A-Winter_2012.jpg

No comes the hard time riding:Punk:

greetings, Wolf

TheRealWolf
17th November 2012, 23:49
Hello,
here is the picture of the spacer which hold the tank:

http://www.repage8.de/memberdata/keep-it-kiwi/ASpacer.jpg

Greetings, Wolf

cave weta
18th November 2012, 08:04
Hello,
a little update while I'm working on my bike: I raised the rear end of the tank about 6 cm to get it paralell to the frame. Now i have to raise the seat at the front end for a little so the line goes straigt from front to end.

http://www.repage8.de/memberdata/keep-it-kiwi/GN250MaoriTanklinie.jp

Greetings from beginning autumn at lake constanze, Wolf

That is just what it needed- instant transformation
!

underdaseas
30th November 2012, 00:17
Hello, I have been admiring your GN250. I just purchased a 1991 GN 250 Suzuki and would love to learn how to take it apart and put it back together again. I live near Kaiserslautern Germany and am an American. Would you like to teach an old lady with a fair amount of mechanical ability the ins and outs of the GN 250?

TheRealWolf
27th December 2012, 04:25
Hello,
because I live near lake Constance it will be difficult to meet for rebuilding your GN.
Yesterday I tested m moddings at the careburator in Combination with a new intake Air filter and so I got my GN on a test drive up to 135 km/h on a light downhill.:2thumbsup


http://www.youtube.com/watch?v=sMYTmvKJGCk

At the end of this video you can see my GN250, it is no fake. The Windshield is not as big as the camera shows, ist because of the wide angle I used. Maybe next year I try the 300ccm kit and an other clutch.
Greetings from Germany, Wolf

ducatilover
27th December 2012, 07:04
Go the GN!

With the 300cc kit, be very careful installing the locating dowels under the barrel/cylinder and measure their outer diameter before installing, anything below 12.95mm and the cylinder can twist off center, which will do some damage.

I learned the hard way that not all Chinese made dowels are very good, I ended up using some original Suzuki items.

Or... you could just fit a much larger engine like I have

JMSR
13th January 2013, 08:36
Howdy all, I've been lurking around for too long and thought this thread was GN cool enough for jumping in, showing off, and asking questions. Nice bike RealWolf and thanks for adding to the inspiration, the discussion about the spacers under the tank helped heaps. I even went as far as to put sandwiched spacers in the front seat mount to match. I hope you don't mind me hijacking your thread but I thought the title was generic enough for more than 1 bike. My build is more scrambler than cafe racer due to my 6ft frame but the principles are the same, just taller. Here's the build so far, early days yet and plenty of questions to come. Mods, in chronological order, are: 50mm tank and seat spacers (1st photo), straight bars and new tail light, seat cut and shaved (much easier than anticipated), trial tank stripping (looks great most angles but dominates the bike side on, black tank ordered), new rear guard rear mounting bolt holes drilled to lift tail (in line and under original holes, close to the edge gives nice lift), guards and rear shock shrouds cut down, black tank and smaller indicators, new Cycleworks full exhaust system (moved the needle to richen it up to suit) and moved tail light back, removed centre dash between dials and lowered front end 38mm (attacking corners feels much better with this mod). LOTS more mods to come including full engine mods and hot carb. This is easily the most fun I've ever had with 3 weeks and $800!

JMSR
13th January 2013, 08:40
Ahem, more than 6 photos. :shifty:

ducatilover
13th January 2013, 11:23
Looks cool dude.
Be warned, get any more power from it and you'll destroy the clutch. :laugh: don't ask how I know...
For carbs, be careful what you choose, I'd personally try find a Mikuni TM32 for it
You'll want to have the block decked for more compression and you can bore it out to run a DR350 piston, I've got a motor taken to 300cc, but you can go bigger. You can safely run an 84mm bore in it, if you set it up correctly (that leaves 3mm of cylinder liner)
Then if you are to cam it, you'll want to ditch the valve springs, they're not the best and are probably already out of spec...
Then port work, this helps 'em a bit if you keep it simple and smooth the ports out, they're rough as guts and not matched.
You'll need to do the bearings in the motor and make triple sure you clean the oil galleries out (the bearings from factory in Jap ones didn't cope to well with my mods, the Chink ones are worse)

You'll want to upgrade the clutch springs, they're made of cheese.
It's not likely to ever want to rev, the crank and flywheel set up is fucking heavy.

JMSR
13th January 2013, 14:40
Hey there, that's all good news! No bad surprises there for sure. I've gone far deeper with mini engines. I'm wasn't going to go any higher than 300cc because I wanted to keep it bullet proof and have yet to decide on re-bore or piston kit but yeah clutch is going to be done with the first engine mods for sure. Thanks for the tip on the carb, I'll start having a look around. You know a good cam guy?

ducatilover
13th January 2013, 16:25
There's an excellent guy in Palmy who does great work for a good price, I forget his name though

I'd suggest re-bore and running a DR350 piston, or an early GSX-R 1127 one, but with the Gixxer one you'll need to run teflon caps on the gudgeons, because the 1127 runs a different size pin. You could also look at O/S bandit 1200 slugs, but the early 1127 is flat topped and you don't need to cut in valve reliefs.

I have a spare 300cc kit, but the piston wore out of round when the block locating dowels decided to be crap. :laugh: so it could be taken out a little and fitted with a DR350 piston.

It will be reliable at 84mm bore if you're got 'er set up correctly. I was contemplating builing one with an alloy piston from a BMW M50B25, but can't be fucked, the DR600 GN I have should work a wee bit better

I've got a brand new cam if you're after a fresh one for a re-grind. I've got GN bits all over my garage...

JMSR
13th January 2013, 17:01
Hmm re-bore and DR350 piston sounds like me. We have a couple of really good engine specialists in Dunners that I would trust with that. When you say 'set up correctly' is there a secret knack here or just the usual 'don't be a plonker' stuff? I did find the TM32 Flatsliders on amazon for a starter so I know they're a go. I'll pass on the cam at this stage thanks but will keep it in mind. Oh and a GN600!! That's just asking for a flux capacitor! And I ain't talking washing powder.

ducatilover
13th January 2013, 20:14
Hmm re-bore and DR350 piston sounds like me. We have a couple of really good engine specialists in Dunners that I would trust with that. When you say 'set up correctly' is there a secret knack here or just the usual 'don't be a plonker' stuff? I did find the TM32 Flatsliders on amazon for a starter so I know they're a go. I'll pass on the cam at this stage thanks but will keep it in mind. Oh and a GN600!! That's just asking for a flux capacitor! And I ain't talking washing powder.
Not really much secret knack, just not revving too hard and keeping the oil pressure and temp reasonable, plus do not run it too lean, it'll melt a piston. A DR piston is miles away from the limit of how far you can go though. But, from my experience, you won't get a heap of power from it without reshaping the squish area in the head, or having a much, much lighter crank/flywheel. I was building my 300 to try get 30hp, it went pretty well for what it was, but it shat the bottom end and then punched some valves, oops!

I can sell you most parts you'll want, have a new cam chain, new cam, good cam sprocket (these do wear, I have a spec for them written down at home, can get it to you next week) good tensioners. A bored out block with 1mm taken off the base, so with a DR piston you'll be at around 10.5:1 comp. To run a DR350 piston the block I have needs to be taken out another 1mm, it was running a GSXR1127 piston, but the dowels were undersized (12.95mm, should be more, OEM are 12.97) and it twisted and split an oil control ring during run in

But as I've said, standard roller bearings do not like high comp.
276252 here's the state of the GN6 a few months ago when I was last home :niceone: should be a giggle when I've finished it, less spastic than the other toy.

ducatilover
13th January 2013, 20:17
Oh, and with a TM32, you'll have to run a different intake rubber as the standard carb is a BS34SS and has a larger external diameter. If you find an intake runner from another bike that runs a TM32 then make an adapter plate, you'll be sweet

I have some Kawasaki ZZR400K rubbers for the CVKD32, may work, I'll give you one if you need it.

JMSR
14th January 2013, 21:21
Ok so not so much secret knack but more like a series of small, secret explosions :laugh:. I still want it reliable through the rev range so I'll stick with 300cc and a head job. If I have to worry about heat and revs then it wouldn't be in the spirit of the bike I'm going for.

Is lightening and balancing the flywheel and crank shaft an option? Made my last mini sing at high revs.

Was thinking about the carb and it should be tunable from 250cc-350cc to cover every outcome. I'm guessing Mikuni would have set up for the TM32-1 to cover that?

And for sure I'll look your way for parts and knowledge in the future! Great to get to know someone who has been there, done that, got the parts.:niceone:

ducatilover
14th January 2013, 21:29
Setting the carb up is piss easy, I had mine on the BS34SS and only needed to go up 2 jet sizes and raise the fuel level, no needle change or anything

They don't rev well anyway and I wouldn't bother touching the crank, too much money and then you'll have to either remove the balance shaft or have it balanced to the bastard.

There's really only so far you can go with such a shit motor with roller bearings

It's all a laugh though, I had a ball on mine, would hop on it instead of the ZX6 most times. Will be even better now :bleh:

JMSR
14th January 2013, 22:38
:laugh: The motor's not that bad. I love how the whole GN principle seems to be a fine balance between cheap and fantastic. Know what you mean about having a ball. Spent an hour riding around the Otago peninsula testing if I like the lower forks (Don't know about you but I thought the bike was much keener in attacking corners). That plus the new exhaust made me just not want to go home!

What set up would you use in the standard carb with a pod filter, the baffled free flow exhaust, and standard piston? A nice set up to keep me happy tweaking while I'm sussing the bigger things out in other words.

ducatilover
15th January 2013, 11:44
Mine has the front lowered, just for the looks. They scrape the pegs/run out of grip so fast I'm not too worried about trying to make it handle better, a set of sport demons is the best mod you can do on one.

On the stock carb I was up a jet size or two, can't remember what sizes they are, I think standard is a Mikuni 130.
I have a whole bunch of Mikuni jets at home for a standard carb.

The difference with a hacked up standard exhaust is really not noticeable to me. I'd just get it in tune and beat the shit out of it

highace10
19th February 2013, 22:00
Thought i would drop in and post a pic of my GN that is still in the works.

Still have a few things to do...main ones being:

Somehow changing the fork oil to a higher weight. Hopefully stiffen things up a bit

and get the damn thing going, especially after ive cut out the airbox. CV Carbs and pods dont mix apparently.

Ace

ducatilover
19th February 2013, 22:10
CVs and pods aren't great but I had mine running on a foam pod and it was fine. I've got a standard airbox with a brand new OEM filter here in a box somewhere

Very neat looking GN, good to see another with wires!

highace10
19th February 2013, 22:14
Ive been doing a bit of reading about the CV pod thing...not a lot of good info out there. Going a foam pod or using the K&N pod helps things a bit.

The wires are looking great...thats why i bought the 92..

Rejetting should be fun...

Any idea on how to take the top cap of the forks? It looks like it has a small keyway for a special tool...i have no idea

ducatilover
19th February 2013, 22:21
http://dl.dropbox.com/u/26633588/GN250%20Manual.pdf here's my copy of the owners manual
Can't remember un doing the fork caps on my last GN, but I think they have a circlip just above the cap?

Tuning it is piss easy mate. I just shimmed the needle and had a 134, or 136 jet in it, ran fine on a high comp 300cc motor

highace10
19th February 2013, 22:32
I dont rememebr a circlip..hmmm

It looks like a cap with a small round indent at the top with a small key way section...

Know of any place to get jets for the carby? I only have a 140 and 145 main jet. Mind you i dont have the stock exhaust anymore.

Cheers

Ill take a pic of the fork tops tomorrow if that helps

ducatilover
19th February 2013, 22:43
eBay. Buy mikuni or factory pro numbered jets, Keihin and Dynojet will fit but use different numbering :niceone:
I have a GN in my garage, so I can have a look at the forks (mine are in need of a rebuild anyway)
Here's my little toy if you're interested http://www.customfighters.com/forums/showthread.php?p=1217516#post1217516

highace10
20th February 2013, 10:26
Ebay does seem to be the way to go for jets. I'll probably pick up a few and see how it goes.

Nice GN. Tanks looks cool, what's it off?

ducatilover
20th February 2013, 10:36
Cheers, it's a GS450 tank, needs the extra capacity, I don't think a standard tank will last long with that motor, plus the standard tank looks gay :lol:

It looks like you just drive the cap out with that little keyway on the forks.
I'm going to design a preload adjuster for mine, just because I can.

highace10
20th February 2013, 11:03
I thought I recognised the tank.

It's an odd setup that key way.. There must some special tool?

After some reading ill probably shim the springs and try some heavier weight oil.

ducatilover
20th February 2013, 11:11
I did them on my old GN and I'm pretty sure I used a flat blade screw driver and hammer to tap it around

Don't go too far with spacers because the srings will bind under compression.
They take 10w oil as factory, much heavier makes the damping action slow and weird

highace10
20th February 2013, 19:22
I thought the same thing, flat blade screwie and a hammer but its a mighty small key way...

Ive read shimming up to an inch or so should be fine...I guess ill have to see when to finally get the thing going.

ducatilover
20th February 2013, 19:42
My old one had 20mm shim and 15w fluid, still handled like a heap of shit
The only way to make it handle is brace the frame, put new forks and shocks on and brace the swing arm

Or put a DR600 motor in it and leave it stock

highace10
20th February 2013, 19:52
hahahaha well it seems im up shit creek then

Did you use PVC pipe as the shims?

ducatilover
20th February 2013, 20:04
I had some random alloy blanks floating around that I threw in there :niceone: but really, the spring rates are shit and the "valving" is a joke

highace10
20th February 2013, 20:11
Ahhh good to know...as long as it goes to be honest

ducatilover
20th February 2013, 20:31
As long as it's a cool looking GN :D

highace10
20th February 2013, 20:55
and that it is...a cool looking GN. Especially when its done..

ducatilover
20th February 2013, 21:16
Yours should look sweet :2thumbsup

JMSR
23rd February 2013, 09:03
That's fantastic work highace10! Brilliant job on the frame.

Is it my imagination or have you lowered the trailing arm past the clash point on the right side pillion peg bracket? I'm interested in hearing how others have tackled this before I go cutting the clash point out and welding in a new section between the peg and exhaust mount.

The wheels look great. I've just started reconditioning a set of wire wheels and am busting to fit them. Weeks away yet though.

As for the power, don't worry there is a small spark to the GN. I've been chatting to a couple of guys from the US and China. Both from serious engine tuning companies (1 holds/held the record for 125cc 2 stroke 1/4 mile at 10.6s!!!). They both pan the GN, pointing out the dismal max valve lift causing a bottleneck for gases making it a poor choice for competition tuning. BUT they have both played with them and succeeded in going over 30hp at the back wheel and confidently talk of a reliable long life motor putting out between 25-28hp in the upper half of the rev range (stock is between 12-16hp in the middle. Manual says 20-22hp but that's at the fly wheel and probably typically optimistic) without too much effort. That sort of hp on a lightened GN would equal a lot of fun for street bike, sure, not competition grade fun, but fun non the less.

highace10
25th February 2013, 22:12
I ended up just cutting the bracket off and rewelding what was required to mount the exhaust? If you're interested in can post a pic of what I did. The issue I'm having now is that the swing arm is probably too far with that length shock. The chain has very little clearance from the swing arm, prob about 5mm with no weight on the bike. With me sitting on it, it improves a bit. I'm going to try and find a shorter set of shocks (maybe 14inch) and give the chain some clearance. Other than that I don't see any more problems....touch wood.

I now have my tank and seat painted and all the parts needed to finish this bloody thing. All elctricals have been relocated to under the pod on the rear section and my K&N oval pod filter will be going in very soon. I'll then get round to sorting out the front suspension...that should be fun.

This Thursday I will hopefully great some life into it and finally hear it for the first time time in 3 months. Maybe a ride of everything goes well.

Gonna need some luck though

An upspec GN engine would be nice! Maybe something to think about later on down the track.

JMSR
26th February 2013, 18:08
I'd like to cut my peg brackets off but I'd have to have a yarn with local the garages to see if they'd pass it without a frame mod cert or even see if they consider my modded seat single or double.

Keep me informed of your progress with the pod filter. I'd like to do the same and it would be great if somebody walked out into the minefield first. Still I've heard a good few people argue in favor with good gain so there must be a trick or two.

ducatilover
26th February 2013, 18:16
Yup the GN does need more lift, but I'm not certain about putting more stress on the standard valve springs (they're pathetic) or the rockers. The biggest restriction that's easy to fix is the exhaust ports, they're not matched, they're disgusting. :facepalm:

If you make any frame mods look factory you may get away with it

JMSR
27th February 2013, 18:17
Yep, after market springs will be a must. Web Cam Racing Cams do 2 stages of cam and valve spring kits for the DR250 (82-85) but I've been snooping elsewhere. I'm getting my cam from the Devil himself! Only cost me my soul so far but I figure the GN is worth it. Can't say anymore until it's paid for and ordered though. Talk is cheap as they say.

I have to get that back end up at some stage so the pegs may come off yet. Just have check a few things out first. Don't tempt like that though, every night I talk myself out getting the cutting disc out.

Has anyone looked into the wiring of a rear rim onto a front hub (disc) to have a fatty front tyre like this guy http://www.youtube.com/watch?v=jXfcXSiI9cQ ? I'm more than a little interested in doing this myself.

ducatilover
27th February 2013, 18:35
I'm going to be lacing a new front rim on mine.
I've been considering getting two 17 inch rears from a DR and doing it so I have the ability to have pretty tyres!

The 18 front is way over the top really.
I've also been thinking of throwing on my spare set of ZXR400 forks

JMSR
27th February 2013, 18:57
2 17s would make a sweet looker for sure!

Interesting bout the forks. It's a long term mod for me but on the list for sure. It's starting to sound like there are some good options.

ducatilover
27th February 2013, 19:17
I'd love to get the forks/brakes off an old GS twin and mount them on my wires, it'd be rather neat!

highace10
7th March 2013, 15:23
Well... Now the problems start. Bloody oil filter cover cracked and pissed oil all over the driveway. Another is on order. The bike idles fine but on application of throttle she hesitates a bit. Jets will hopefully help riven her up a bit.

I've also just order some new main jets so they hopefully won't take too long to get to me. Received word from another bloke that he shimmed his suspension 1-1/4 inches and redid the fork oil, works a treat. I'll have to try it.

JMSR
9th March 2013, 08:30
Sorry to hear about the cover. At least it's an easy fix thanks to it being the bike it is. What did the bloke use as the shim?

ducatilover
10th March 2013, 13:58
Well... Now the problems start. Bloody oil filter cover cracked and pissed oil all over the driveway. Another is on order. The bike idles fine but on application of throttle she hesitates a bit. Jets will hopefully help riven her up a bit.

I've also just order some new main jets so they hopefully won't take too long to get to me. Received word from another bloke that he shimmed his suspension 1-1/4 inches and redid the fork oil, works a treat. I'll have to try it.

Sucks about the cover, I could have sent you one for the cost of shipping :cool:

My '04 GN was binding the front springs with that much spacer
I've been meaning to design a preload adjuster for mine, I reckon it'd be a cool feature and good for a giggle.
Have to find somebody to let me use their lathe lol

highace10
11th March 2013, 14:26
I found a new cover from a wrecker in Western Australia. $20 to my door. The bloke used washers. He was nice enough to drop some off in my letter box about an hour ago. ;)

I'll try an inch first and see how it is.



Sent from my HTC Velocity 4G using Tapatalk 2

highace10
14th March 2013, 15:07
Got the cover, fitted nicely.

Also got the new main jets and thew in the 135. It idles nicely and revs well, haven't taken it for a ride yet. Maybe this afternoon.

pondyrock
10th April 2013, 18:21
seat cut and shaved (much easier than anticipated), trial tank stripping (looks great most angles but dominates the bike side on, black tank ordered), new rear guard rear mounting bolt holes drilled to lift tail (in line and under original holes, close to the edge gives nice lift), guards and rear shock shrouds cut down, black tank and smaller indicators, new Cycleworks full exhaust system (moved the needle to richen it up to suit) and moved tail light back, removed centre dash between dials and lowered front end 38mm (attacking corners feels much better with this mod). LOTS more mods to come including full engine mods and hot carb. This is easily the most fun I've ever had with 3 weeks and $800!

Hey mate, do you have any more detials on how you cut down your seat like that? Looks great and would like to do the same to mine, including the shortening of the rear guard?

Cheers,

Matt

highace10
10th April 2013, 20:09
All done. Running nicely now after a couple of small things.

:-)

http://img.tapatalk.com/d/13/04/10/ypyzagy7.jpg

nzmikey
11th April 2013, 11:17
Thought i would drop in and post a pic of my GN that is still in the works.

Still have a few things to do...main ones being:

Somehow changing the fork oil to a higher weight. Hopefully stiffen things up a bit

and get the damn thing going, especially after ive cut out the airbox. CV Carbs and pods dont mix apparently.

Ace

Are you running clip on's on that ? If not how the hell did ya do that ?
:eek5:

JMSR
11th April 2013, 22:16
Highace that looks preeeeeeeeemo!!

Matt, Pulled the staples on the cover then used a wide flat handsaw for cutting the plastic and the foam. The plastic cuts easily with a sharp saw. I cut the back off to the molding for the rear mount, and drew a horizontal line from the bottom front corner along the side then cut it with the saw teeth flat along the line for a good straight cut. You'll be cutting through the foam at the same time so it'll act as a guide for the saw. I should also mention I have a 50mm ply spacer between the plastic and front mount hook which changes the profile a little and and matches the spacer under the back of the tank. Smooth of the edges with a sanding disc or block. Lay the saw flat on the lower part of the seat and slowly cut with broad strokes the top off the pillion section. Round off the corners of the foam. When putting the cover back on use the pattern as a guide. Instead of stapling I used M3x6 long self tappers with wide washers and pre-drilled a pattern of about 60 around the underside. This would allow for adjustments and future covers not to mention it's near impossible to staple that plastic! Good luck.

ducatilover
11th April 2013, 22:55
I've got a normal staple gun from Bunnings, has done me about 5 seat covers and it managed fine when I did the GN seat chop last year

I better get around to finishing my GN. NOS piston for the DR600 motor in it arrived last week, so I might manage to get the motor done tomorrow.

JMSR
12th April 2013, 07:32
Hmm I tried a good industrial staple gun but it must have been poos.

Wow exciting times with the GNs! I wish I could be as excited with mine but customs is dragging their heels on releasing my go faster bits. Grrr.

ducatilover
12th April 2013, 11:20
Hmm I tried a good industrial staple gun but it must have been poos.

Wow exciting times with the GNs! I wish I could be as excited with mine but customs is dragging their heels on releasing my go faster bits. Grrr.

Are you using decent staples? I don't remember the brand mine are, but they're not el-cheapo ones, cheap ones just fold on themselves

:clap:What go-fast bits have you got yourself?

pondyrock
12th April 2013, 17:57
Highace that looks preeeeeeeeemo!!

Matt, Pulled the staples on the cover then used a wide flat handsaw for cutting the plastic and the foam. The plastic cuts easily with a sharp saw. I cut the back off to the molding for the rear mount, and drew a horizontal line from the bottom front corner along the side then cut it with the saw teeth flat along the line for a good straight cut. You'll be cutting through the foam at the same time so it'll act as a guide for the saw. I should also mention I have a 50mm ply spacer between the plastic and front mount hook which changes the profile a little and and matches the spacer under the back of the tank. Smooth of the edges with a sanding disc or block. Lay the saw flat on the lower part of the seat and slowly cut with broad strokes the top off the pillion section. Round off the corners of the foam. When putting the cover back on use the pattern as a guide. Instead of stapling I used M3x6 long self tappers with wide washers and pre-drilled a pattern of about 60 around the underside. This would allow for adjustments and future covers not to mention it's near impossible to staple that plastic! Good luck.

Thanks for the write up. I'll give it a try, I like that you've actually cut away the plastic along the sides and the back making it shorter.

Did you just move your rear mudguard up and drill new holes to make it shorter?

JMSR
13th April 2013, 08:00
300cc piston and barrel, hot cam and rockers from these guys http://www.xlitemoto.com/index.html. He's also just told me they're now dealing with 400cc kits.

Below, word for word, is the advert for the cam. Man I laughed! Then I saw the profile. Then I saw the graph. Then I sorted it.

The GN250 is painfully slow , no power at all , even GN400 was sluggish piece of s*#t, let alone GN250 , even GN125 feels faster , so if to make one Camshaft for this model , it better make it fast , or not make it at all :

this not a normal RACE cam , it put any RACE s#*t into shame , we not BS you .. look , lobes almost Square , so it has faster ramp then NASCAR , more duration then a GP bike , you not believe GP bikes not use big durations .. so it is for street , designed to work with stock head and valve train... should clear stock piston too .. check all clearances.

cylinder can be enlarged a lot on this model , we tried different sizes but valves too small , it run of steam at high rpm therefore Megaphone is a must for big CCs

can be taken to about 375 but only 300 kit mass produced , if you want one , its $150 for full kit , no case boring required .., others sizes never mass produced so not exist for sale , this model not popular in china because of high cost , so we can not mass produce any parts for it. either , will not do further experiments and testing on it.either ..

this cam is ONE OFF , sorry for high prices , only 1 part exists in the world , not mass produced ...


Matt, yep I just drilled new holes for the indicators. Under the existing ones there's a nice little clear area to drill. Be careful not to raise it too high, allow for the nearby crossbar. Then I just used masking tape from a chosen spot in the center of the guard below the tail light to just behind where you have just drilled to mark my cutting line to reshape the guard. A steady hand with a 1mm cutting disc on the grinder followed by a wide, coarse sanding block was all I used. I also drill holes for the new tail light under the old ones to make it lower and more horizontal. Zoom in on the previous pic and the two below as a guide.

ducatilover
13th April 2013, 16:10
Please tell me that cam is some sort of joke?

:lol:

JMSR
13th April 2013, 17:31
Win or fail I'll be the one who found out:devil2:.

ducatilover
14th April 2013, 21:29
I'll send you a free cam and assorted parts once you snap valves and springs, free but only if you video it. Or take pictures of it throwing small engine parts at somebody on a dyno

I'm going with, valve hit piston, bend valve, crack rocker (at the least) and possibly snap the guide (mine managed that)
Or it simply won't start



I'd also like what drugs that fella is on, so I can stay away from them lol

JMSR
15th April 2013, 19:42
I'm not toooo worried :brick:. I've had good advice from Dunedins finest bike mechanics and old boy bikers thanks to being a barber. Not to mention a couple of race engines for cars under my belt thanks to my Mech Eng degree and 12yrs machinery design. Throw in a brother in law who builds trail bikes for VMX including the old DRs. So as I say,I'm not toooo worried. Anyway Xlite have had the world record for 1/4mile 125cc 2 stroke at 10.6s!!!! So they shouldn't be slouches surely.

One thing that is interesting, and this all agreed upon after much deliberation and investigation, is the use of standard soft springs. How's that for twisting your noodle. It's what Xlite recommend. The bike mechs agree and I think it adds up so it's chocks away on this build for sure!

ducatilover
15th April 2013, 20:05
I can't wait.


I shall install some square cams in the next drag car I work on and all the rally cars I'm booked in to work on this year :bleh:


P.S it won't work.

JMSR
16th April 2013, 18:32
Lol touche. I'll video for sure, just for the tiniest teeniest chance I need some parts.

It's a long shot, but the GN is an easy fixer upper so why not have some fun.

ducatilover
16th April 2013, 18:54
That's the way bro! :Punk:

I was going to pull the DR6 motor and finish it today, but I got some metal and rust in my eye and the doctor fella had to put me out and get some sharp tools in there :facepalm:

Erelyes
16th April 2013, 19:27
To get the most out of your square cams tho you need to upgrade to square wheels.

highace10
17th April 2013, 16:19
Standard clipons were used, front shocks lowered through the clamps by about 2 inches.

A mate of mine has just fitted the 300 kit and so far is enjoying it. Still needs some run in time but so far he has noticed a healthy dose of torque down low.

$200 for the kit... Can't complain.

ducatilover
17th April 2013, 20:25
Standard clipons were used, front shocks lowered through the clamps by about 2 inches.

A mate of mine has just fitted the 300 kit and so far is enjoying it. Still needs some run in time but so far he has noticed a healthy dose of torque down low.

$200 for the kit... Can't complain.

Buying direct from China mine was around $80 US + shipping. :Punk:

I reckon, get a cheap piston that's around 10mm O/S of standard, have a machinist take out your original barrel and then run teflon dowlels in place of gudgeon clips and you're away.

Might do it to another GN one day, just for shits and giggles

highace10
17th April 2013, 20:42
Buying direct from China mine was around $80 US + shipping

Do you still have the details of where you bought it from?

Cheers

ducatilover
17th April 2013, 20:50
www.c2345.com and it took a bit of navigating, I'm not sure if they still stock them
Aliexpress do the 78mm piston and rings for $40USD or so
You can also go with a few other pistons, like an O/S GSX-R1100, Bandit 12 etc, the Busa piston would need machining on top, so not much point going there

ducatilover
17th April 2013, 20:53
http://www.c2345.com/product/7017406180/Wangjiang%20Suzuki%20factory-%20GN300%20efficient%20power%20components%20availa ble%20for%20sale here you go mate

When I got mine it was $83 USD:facepalm:

JMSR
19th April 2013, 18:50
My bits arrived this week. OoooooooooYeaaaaaaaaaah!

ducatilover
19th April 2013, 22:49
Pics :niceone::niceone:

highace10
19th April 2013, 23:37
Pics for sure!

That 300 kit, would it be the same one that is available on Ebay? I cant imagine there being too many places that manufacture that gear.

ducatilover
19th April 2013, 23:42
I would expect it to be the same one.
Just measure the dowels for the barrel to engine cases, no less than 12.95mm, otherwise your block may twist off a little, and make sure you set the barrel nuts (2 m6 on the RHS) to the correct torque when the manual tells you to.
A few people get base gasket leaks, then crank the M6 nuts down and it pulls the block over and eats the piston lol

highace10
20th April 2013, 12:23
Great info, that's the sort of stuff I'm after. Having never taken an engine apart those details will help.

Thanks

Any more tips? :D

ducatilover
20th April 2013, 22:29
Millions of tips! Best of all, follow the owner's manual to the very last word.

bosslady
21st April 2013, 07:57
Highace that looks preeeeeeeeemo!!

Matt, Pulled the staples on the cover then used a wide flat handsaw for cutting the plastic and the foam. The plastic cuts easily with a sharp saw. I cut the back off to the molding for the rear mount, and drew a horizontal line from the bottom front corner along the side then cut it with the saw teeth flat along the line for a good straight cut. You'll be cutting through the foam at the same time so it'll act as a guide for the saw. I should also mention I have a 50mm ply spacer between the plastic and front mount hook which changes the profile a little and and matches the spacer under the back of the tank. Smooth of the edges with a sanding disc or block. Lay the saw flat on the lower part of the seat and slowly cut with broad strokes the top off the pillion section. Round off the corners of the foam. When putting the cover back on use the pattern as a guide. Instead of stapling I used M3x6 long self tappers with wide washers and pre-drilled a pattern of about 60 around the underside. This would allow for adjustments and future covers not to mention it's near impossible to staple that plastic! Good luck.

that's a sweet looking exhaust you've got there!

JMSR
21st April 2013, 15:42
Yeah exhaust is pretty sweet. Should really be a good megaphone but this was available ready made, off the shelf to your door from CycleWorks on TradeMe. Goes much better than stock being a free flowing one-piece, and sounds great too. Removable baffle for frightening the neighbors.

Here's pic of bits.

bosslady
21st April 2013, 15:54
Yeah exhaust is pretty sweet. Should really be a good megaphone but this was available ready made, off the shelf to your door from CycleWorks on TradeMe. Goes much better than stock being a free flowing one-piece, and sounds great too. Removable baffle for frightening the neighbors.

Here's pic of bits.

Is that the right pic?

JMSR
21st April 2013, 16:09
For an earlier request.

ducatilover
21st April 2013, 22:34
Here's pic of bits.

Good stuff man. I had my 300 barrel decked by 1mm to get compression up a bit, easiest to machine it off the base gasket face.
The compression and 300 kit makes enough difference to fry the clutch during run-in... :nono: but shimming the springs helps, or fitting something better (I think my ZZR400 springs would fit, otherwise I have a spare set of DR600 ones, can check if the will fit)

I'll build another GN motor up when I find one cheap enough and I'll match the head to the larger bore (will have 2.5-3mm liner wall depending on which piston I can get with the correct compression height) and see how much it helps.
It may even be possible to modify an old DR/SP head of some sort to fit it
Then find somebody who can press out the crank pins and fit webs from a DR in to it...


Just for lulz

Smifffy
22nd April 2013, 16:39
Just spotted this today, a couple of interesting ideas there. I like the look of the 'finished' job.

http://www.dotheton.com/forum/index.php?topic=46585.0

kiwikk
2nd May 2013, 21:58
I'd like to cut my peg brackets off but I'd have to have a yarn with local the garages to see if they'd pass it without a frame mod cert or even see if they consider my modded seat single or double.

Hey JSMR, How did you get on with this issue?
I was thinking I might be able to 'pursuade' :msn-wink: the peg bracket to shift over the necessary 12mm or so. Even if this is successful and not fatal then the next issue is sourcing cheap 14inch spring shocks in NZ. I'm going to check out dirt bike breakers this weekend.

highace10
3rd May 2013, 09:21
Rearsets are on their way :-)

If you're after shocks, try out Tecshox. I got my longer shocks for $80 posted to my door. I've got his email somewhere, I'll find it and post it up.
He is over here in Australia but I don't think postage woukd be too much to NZ.

kiwikk
3rd May 2013, 21:44
Howdy all, I've been lurking around for too long and thought this thread was GN cool enough for jumping in, showing off, and asking questions. Nice bike RealWolf and thanks for adding to the inspiration, the discussion about the spacers under the tank helped heaps. I even went as far as to put sandwiched spacers in the front seat mount to match. I hope you don't mind me hijacking your thread but I thought the title was generic enough for more than 1 bike. My build is more scrambler than cafe racer due to my 6ft frame but the principles are the same, just taller. Here's the build so far, early days yet and plenty of questions to come. Mods, in chronological order, are: 50mm tank and seat spacers (1st photo), straight bars and new tail light, seat cut and shaved (much easier than anticipated), trial tank stripping (looks great most angles but dominates the bike side on, black tank ordered), new rear guard rear mounting bolt holes drilled to lift tail (in line and under original holes, close to the edge gives nice lift), guards and rear shock shrouds cut down, black tank and smaller indicators, new Cycleworks full exhaust system (moved the needle to richen it up to suit) and moved tail light back, removed centre dash between dials and lowered front end 38mm (attacking corners feels much better with this mod). LOTS more mods to come including full engine mods and hot carb. This is easily the most fun I've ever had with 3 weeks and $800!

JMSR, love what you've done for your $800 ! :niceone:
You've done just about everything I'd planned for my old '92 wired GN
Seat looks great. Is the 50mm raise at the front enough for your 6ft ?
I'm going to look at trail bike seats which are slimline and give extra height. I'd have a go at copying your seat mod but my seat covers knackered.
I'm only 5ft 8 but being an ex trail bike rider, I'd like to get the whole bike higher by raising the back end a bit with longer shocks, for which highace10 is looking into AU suppliers. I've also encountered your issue about that stupid swingarm clash with the right side rear peg bracket restricting shock height.
Did you do anything about this or stick with the stock shocks?
Any chance of providing supplier details for those natty indicators and back light ?

kiwikk
3rd May 2013, 21:48
Rearsets are on their way :-)

If you're after shocks, try out Tecshox. I got my longer shocks for $80 posted to my door. I've got his email somewhere, I'll find it and post it up.
He is over here in Australia but I don't think postage woukd be too much to NZ.

Cheers mate :niceone:

highace10
3rd May 2013, 22:11
Actually it's probably easier to look him up on the aussie ebay. They have a range of lengths and looks. Should help you out. If you have trouble finding them let me know.

JMSR
5th May 2013, 08:38
Hey JSMR, How did you get on with this issue?
I was thinking I might be able to 'pursuade' :msn-wink: the peg bracket to shift over the necessary 12mm or so. Even if this is successful and not fatal then the next issue is sourcing cheap 14inch spring shocks in NZ. I'm going to check out dirt bike breakers this weekend.

It's a possibility, I had a look a while ago and thought it could be bent with a little heat, I wouldn't do it cold. Let me know if you give it a go.
The extra seat height is very noticeable and well worth it. The MX bars have been just has much help in that regard too. My legs and arms don't feel cramped at all. With the original set up I was sitting too far back and over bending my knees, wrists and elbows, felt horrible. Have you seen the seat for the TU250 Grasstracker Bigboy version? If you haven't already seen the Grasstracker, check it out.
All my lights are from Trade Me. I had to use a universal flasher relay ($15 from auto electrician NOT $60 off trade me!). If you change your indicators let us know before you buy the set up. There are a lot of people spending way too much and over complicating this mod. We'll help you with your wire colour matching too (can be a head scratcher).

kiwikk
16th December 2013, 19:42
It's a possibility, I had a look a while ago and thought it could be bent with a little heat, I wouldn't do it cold. Let me know if you give it a go.
The extra seat height is very noticeable and well worth it. The MX bars have been just has much help in that regard too. My legs and arms don't feel cramped at all. With the original set up I was sitting too far back and over bending my knees, wrists and elbows, felt horrible. Have you seen the seat for the TU250 Grasstracker Bigboy version? If you haven't already seen the Grasstracker, check it out.
All my lights are from Trade Me. I had to use a universal flasher relay ($15 from auto electrician NOT $60 off trade me!). If you change your indicators let us know before you buy the set up. There are a lot of people spending way too much and over complicating this mod. We'll help you with your wire colour matching too (can be a head scratcher).

Better late than never....

I bent it cold no problem.

Check out my new project thread: http://www.kiwibiker.co.nz/forums/showthread.php/162506-GN250-Custom-Project-FSM

oh, and thanks for the inspiration :2thumbsup

richisells
10th May 2014, 06:47
I'm in Austria and am also a (ahem) proud owner of a GN250 which i'm going to turn into a flat tracker carablanco style!

Anvil
24th May 2014, 08:16
Hey - thought I'd throw this up on here as I've done a few mods to the girl's GN. Ended up being a real blast to ride!
Dropped the front end about 2" which improved the handling no end. so much better.
chopped the front and rear fenders
clip on bars, between the triples
little led indicators
black wrap on the pipes, black heat paint on the exhaust
smaller tail light
dropped the front light, speedo, ignition barrel. Didn't quite get it as low as I wanted - needed another 1" i reckon. (that's what she said?!)

Anyway - here it is.

Anvil.

haydes55
24th May 2014, 09:58
Nice. You're right about the lights etc. Cluster could do with being a bit lower. To complete the look, get a single seat, ditch the ugly lounge seat. Nice cowling behind a thin single seat will top it off.

ducatilover
24th May 2014, 20:56
Mine with the motor finally mounted. It's light enough that I can lift the whole bike on to the bench :clap:297347

Anvil
25th May 2014, 00:07
Haydee55, she's now sold, but hopefully new owner will sort the the front cluster and seat :)

tomgn
24th August 2016, 23:17
Awesome project man! I would suggest a more distinct paint but that just me! I saw some ideas on http://suzukign.com and I think I am going to try the scrambler style! Can I ask you how many money have you spend till now? My budget is rather small but I am mechanic.


Thanks