Race Bike Rebuild

Show us that box of bits in your shed!
Post Reply
Luders
Avgas Sniffer
Posts: 3926
Joined: Fri Jun 18, 2010 11:29 am
Location: Oxfordshire

Race Bike Rebuild

Post by Luders »

As some of you were after pictures of the evolution of next year's bike, I'm making a start now with this one and we'll go from here.

As you can see, I've started by fitting a ZXR400L front end and I also managed to pick up a few RGV250 VJ22 rear wheels, to benefit from the wider tyre choice.

Many of the guys run on the Michelin SM pre cut slicks, but I've opted for the Michelin PowerOne race tyres. They come in a choice of compound and also make a road version of this tyre.

I've fitted some Jim Lomas stainless steel expansion chambers, with carbon fibre end cans.

Image

Next jobs are to create an under tray for the rear sub frame and make a flywheel cover. The flywheel has gone away for a week with slimming world, so will hopefully come back a bit lighter. I need to make up a gear linkage, a chain tensioner to clear the chain between the expansion chamber and I will make a start on fitting the body work.

Next installment of photos in about two weeks.
User avatar
Howie
Avgas Sniffer
Posts: 2055
Joined: Mon Mar 16, 2009 9:33 pm
Location: East Yorkshire

Post by Howie »

Its looking good Luders,

Are you running the carbs with the trumpets open or are you going to enclose them in a purpose made airbox? I know there was a bit on the forum a little while back where a member had enclosed the trumpets in a larger than standard box but I can't remember who posted the item :oops: sorry, memory is rubbish.

Also I was thinking of going two single lines to my front brake set up on my (yawn) ongoing Kr1s project. Is there any benefit in using the set up on a road bike? Or is it just a weight saving idea on a race bike?

Has the bike got the RGV rear on it in the pic, can't tell because of the angle or is it a Kr1 item? Once again due to lightness? And if you use a 17" rear, how do you adjust for ride height etc or is that taken into account with the rear shock? (R6?)

I'm pretty sure I've read the answers to all these questions before but because I will hopefully have the time over winter to work on my Kr1s, its just nice to know which post they are all in & yes these are all mods I want to do on my Kr1s :oops:

Its been said before but I'll say it again, nice pipes sir 8)
Luders
Avgas Sniffer
Posts: 3926
Joined: Fri Jun 18, 2010 11:29 am
Location: Oxfordshire

Post by Luders »

I will be making a custom airbox from carbon fibre, but it's Mark Jordan who has been working on his and posted some photographs on the forum.

Having the brake hoses running straight from the master cylinder instead of through the splitter is more efficient and I would recommend it for road use as well as race.

The rear wheel in the picture is an RGV 17x4.5 inch rim, so you loose about 12mm of ride height, but gain about 70mm by fitting the R6 shock, I forget the exact numbers.
The key thing is the bike geometry and rake angle, so fitting ZXR forks raises the front height to compensate for what you gain in the rear.

I would always have a smaller rake angle than what it's set from factory, somewhere around 26 degrees, so welcome the overall increase in height from the rear.
KR-1R
Premix Junkie
Posts: 1587
Joined: Wed May 16, 2007 2:24 am

Post by KR-1R »

.
.
I believe the F3 kit has an alternative Steering lock stop (that like the ZXR400 kit) bolts onto where the brake hose splitter mounts on the lower triple clamp
User avatar
JanBros
Avgas Sniffer
Posts: 3306
Joined: Wed Jul 26, 2006 11:50 pm
Location: the land of Francorchamps

Post by JanBros »

Luders wrote: Having the brake hoses running straight from the master cylinder instead of through the splitter is more efficient and I would recommend it for road use as well as race.
performance wise, there is no difference. presure is spread equally throughout the system, presure doesn't know if there are 2 lines or one seperating into 2 :wink:
My ultimate goal is to die young as late as possible !
Luders
Avgas Sniffer
Posts: 3926
Joined: Fri Jun 18, 2010 11:29 am
Location: Oxfordshire

Post by Luders »

So, I've done the gear linkage and made a start with the fairing.

The belly pan was too narrow, so I've had to cut some holes for the spannies to poke throug, otherwise it just wasn't going to go high enough.

I will fibre glass over these later and contour them around the exhausts.

I'm also having to raise the sides which run along the frame slightly, which is why you can see a thin layer of fibre glass fabric there.

The brake reservoir will also need to be lowered a bit to make way for the screen and I can't stand the way the belly pan sweeps back and tries to hide the exhaust, so those will be trimmed right back!

Here's your picture :D
Image
375
Premix Junkie
Posts: 1305
Joined: Fri Apr 18, 2008 9:41 pm
Location: Essex. Depeche Mode, Town

Post by 375 »

Lunders is this a second race bike or rebuild of your original one,

Do the race rules allow you to run with a complete different front end
Luders
Avgas Sniffer
Posts: 3926
Joined: Fri Jun 18, 2010 11:29 am
Location: Oxfordshire

Post by Luders »

This is just a rebuild of my original and the only things you cannot change, is the engine, frame and swing arm.

Although I race with Derby Phoenix, Thundersport GB outline the regulations well and they are similar.

http://www.thundersportgb.com/downloads ... egulations
User avatar
Howie
Avgas Sniffer
Posts: 2055
Joined: Mon Mar 16, 2009 9:33 pm
Location: East Yorkshire

Post by Howie »

the only things you cannot change, is the engine
Can you not tune it then Luders? Or do the rules just apply to 'over bores'?
Luders
Avgas Sniffer
Posts: 3926
Joined: Fri Jun 18, 2010 11:29 am
Location: Oxfordshire

Post by Luders »

Have a look at the technical specs on the link I posted.

You can tune the engines, but I wouldn't be able to fit an H0nda RS250 engine in my bike, or oversize the pistons if that makes sense.
Luders
Avgas Sniffer
Posts: 3926
Joined: Fri Jun 18, 2010 11:29 am
Location: Oxfordshire

Post by Luders »

Image
Progress has been slow lately and I'm currently still working on getting this fairing right. I'm going to cut the belly pan down diagonally from the top piece, where it meets the fairing upper, to raise the ground clearance of the rear and I'm having some upper fairing brackets fabricated from aluminium.
User avatar
Datafunk
Light Smoker
Posts: 45
Joined: Mon Dec 05, 2011 6:28 am
Location: Australia

Post by Datafunk »

very sexy.
1974 Suzuki RL250, 1979 Yamaha XS250, 1991 KR1S, 2006 Kawasaki ZX-6R
User avatar
500bernie
Avgas Sniffer
Posts: 3396
Joined: Mon Aug 02, 2010 10:22 am
Location: Teesside

Post by 500bernie »

Looking good as usual Ben =D>

Will you need such a large gap in front of the bars?

Or are you intending to close it up somehow?

Have you sorted the jockey wheel/guide to keep the chain off the left pipe yet?

Cheers,
Bernie :D
Firecracker Red and Grey C3 300
Luders
Avgas Sniffer
Posts: 3926
Joined: Fri Jun 18, 2010 11:29 am
Location: Oxfordshire

Post by Luders »

I need the space and if you look where the clutch lever ends, you can imagine why on right lock.

I made the first bracket too long and haven't bothered with the carbon since, but I need to make an air box soon, so it will come out again then.
User avatar
JanBros
Avgas Sniffer
Posts: 3306
Joined: Wed Jul 26, 2006 11:50 pm
Location: the land of Francorchamps

Post by JanBros »

are you sure the fairing isn't too much upfront ?

looks like there isn't hardy any clearance between the front wheel and lower fairing ?

nice shape though 8)
My ultimate goal is to die young as late as possible !
Post Reply