Gsxr 750 W Classic TT build

[AndyJackson94]

Hello all. 

After most of my research seems to come from this site anyway I thought I may as well join up! With most of my race season cancelled i thought I would build something ready for next season. whilst the ZXR750 is the more popular and competitive choice, i have always loved my old school suzukis and have a particular soft spot for the Yoshimura F1 bikes of the early nineties so im planning on building a bit of a replica with a view to race it at Olivers Mount and the Classic TT

 

 

I have started with a 1992 W frame and have a swingarm + linkage on the way as well as a K5 rear shock. The plan is to put a K2 750 front end on so i have a bottom yoke on the way. My research leads me to believe that the k2 bottom taper bearing will fit straight in and that I should just need a 32906 top bearing. Can anyone confirm or advise? I have also opted to use a triumph 675 rear wheel so if anyone who has done the swap could point me in the right direction that would be super. 

Pics on the way

Cheers 

Andy

 

[eddiegsx]

Welcome Andy, as you point out racing this year is highly unlikely..

The build sounds interesting pls keep us all posted on progress.

[AndyJackson94]

Just now, eddiegsx said:

Welcome Andy, as you point out racing this year is highly unlikely..

The build sounds interesting pls keep us all posted on progress.

I have my entry in for the Manx GP and so far thats the only race that hasnt been cancelled... Yet... 

[eddiegsx]

2 minutes ago, AndyJackson94 said:

I have my entry in for the Manx GP and so far thats the only race that hasnt been cancelled... Yet... 

We can all live in hope

All the Irish road races are now cancelled with Armoy being the exception.

Not sure if the powers that be would want to let a crowd of road racers (as talented as you all are) loose on the TT circuit without any road time all season. What do you think, or am I just talkin shit?

Hope I'm wrong BTW.

[AndyJackson94]

10 minutes ago, eddiegsx said:

We can all live in hope

All the Irish road races are now cancelled with Armoy being the exception.

Not sure if the powers that be would want to let a crowd of road racers (as talented as you all are) loose on the TT circuit without any road time all season. What do you think, or am I just talkin shit?

Hope I'm wrong BTW.

The ACU mountain licence requires 6 signatures, at least 3 from Jan 2020, so it would be possible but only if the ACU lift the restriction on short circuit events very soon. I doubt the ACU will waiver the licence requirement as thats part of the insurance policy. Im pretty sure i saw a Manx ruling had been put in place that will see all events postponed until october 2020, i very much doubt its going to run, hence spending my entry fees on GSXR bits

[eddiegsx]

5 minutes ago, AndyJackson94 said:

 hence spending my entry fees on GSXR bits

Always a bright side, that's the spirit

[Simbec1863]

Welcome to OSS and good luck with the build,I reckon you’re doing the right thing won’t be much if any racing this season the way things are going.Love that  GSXR I’ve got some pictures of it somewhere as I was lucky enough to be at Suzuka for the 8hrs in 1992 

 

Edited April 11, 2020 by Simbec1863

[AndyJackson94]

1 minute ago, Simbec1863 said:

Welcome to OSS and good luck with the build,I reckon you’re doing the right thing won’t be much if any racing this season the way things are going.

 

Thanks pal, i have my race bike prepped and ready to go just in case but i cant see it happening at this rate! 

[markfoggy]

Great idea, Not sure how late a frame will fit into the regs, but the one that I've based my project around is later and with all the internal bracing. If you want a frame to untack what they put in and add to an early frame I will have one that can be sacrificial shortly.

If it's a braced frame with the swing arm adjuster on the rhs, I have a brand new adjuster and lock nut that I can throw into the cause. 

675 wheels are a very light option and I have a round spoke one that I can give away, has had all the factory marks ground off, but it's straight and ready for powder. Hub is a little wide on them and I'm not sure if they can be persuaded to give you a true chain run and still run a 180 rear. I'm running a different swing arm in mine, so cannot help with exact fitment issues. Get a triumph drive hub though, which are cheap and common to a lot of models and is worth experimenting if I can get this rim over to you. It has a new rear disc with it, the disc size changed when they went to the forged look spoke design.

Talking of swing arms, good luck finding one. The top braced arm that you want is getting rare, but from memory an 1100 is a little longer and might be the way to go for stability on the Island. They seem to have produced a lot more 1100's the model run was much longer.

PM me if I can help. 

 

[markfoggy]

Sorry, just reread you first post, Early frame. 

[davemfox]

Nice mate - I'll keep my eyes open for this at Scarborough.

Dave

[AndyJackson94]

On 4/25/2020 at 5:39 PM, markfoggy said:

Great idea, Not sure how late a frame will fit into the regs, but the one that I've based my project around is later and with all the internal bracing. If you want a frame to untack what they put in and add to an early frame I will have one that can be sacrificial shortly.

If it's a braced frame with the swing arm adjuster on the rhs, I have a brand new adjuster and lock nut that I can throw into the cause. 

675 wheels are a very light option and I have a round spoke one that I can give away, has had all the factory marks ground off, but it's straight and ready for powder. Hub is a little wide on them and I'm not sure if they can be persuaded to give you a true chain run and still run a 180 rear. I'm running a different swing arm in mine, so cannot help with exact fitment issues. Get a triumph drive hub though, which are cheap and common to a lot of models and is worth experimenting if I can get this rim over to you. It has a new rear disc with it, the disc size changed when they went to the forged look spoke design.

Talking of swing arms, good luck finding one. The top braced arm that you want is getting rare, but from memory an 1100 is a little longer and might be the way to go for stability on the Island. They seem to have produced a lot more 1100's the model run was much longer.

PM me if I can help. 

 

Cheers, I’ve got a round spoke 675 wheel now but I will need a spare for wets at some point! 
 

was wondering if the 1100 swingarm was a touch longer. 
 

675 wheel is an easy fit by the looks of it. It’s narrower and is 20mm axle so with a couple of spacers it can be central and with around 4mm machined off the sprocket Carrier You get the chain line. I think you can run a 520 sprocket off a 250 Kawasaki which has a 1mm offset too, more research to be done on that when I find an engine! 

see post below for updates! 

Edited April 28, 2020 by AndyJackson94

[AndyJackson94]

Here we are so far then...

GSXR750 K2 front end in 

675 rear wheel and caliper mocked up, will make up some spacers soon and get a bracket for the caliper slider. (Will do a full write up on this when it’s done) 

more bits on the way.

 

 

[markfoggy]

FYI, the later frames had all that internal casting plated over,  45 degree box web reinforcement of the top rear cross member. Solid, not bolt in tank bracket, plus additional bracing at the headstock. Plus the very last of them had cast plates from the upper rail that picked up on the engine to make it more of a stressed member and to increase lateral stiffness and  longitudinal stability.

The later style symmetrical over braced arm was derived from the kit bikes, evidence of them being employed on your frame year is the SERT bikes.

 

 

[BenedictIreland]

Lovely, I am also building a replica of the same Suzuka bike! Gorgeous isn’t it? 

[Lewi]

Any updates on this, looks a nice build so far 

[Gammaboy]

On 4/29/2020 at 10:53 PM, markfoggy said:

FYI, the later frames had all that internal casting plated over,  45 degree box web reinforcement of the top rear cross member. Solid, not bolt in tank bracket, plus additional bracing at the headstock. Plus the very last of them had cast plates from the upper rail that picked up on the engine to make it more of a stressed member and to increase lateral stiffness and  longitudinal stability.

The later style symmetrical over braced arm was derived from the kit bikes, evidence of them being employed on your frame year is the SERT bikes.

 

 

The later frames were also lighter (thinner sections), which is why they braced to the head to bring the stiffness back up.

[BenedictIreland]

On 4/11/2020 at 9:01 PM, AndyJackson94 said:

Hello all. 

After most of my research seems to come from this site anyway I thought I may as well join up! With most of my race season cancelled i thought I would build something ready for next season. whilst the ZXR750 is the more popular and competitive choice, i have always loved my old school suzukis and have a particular soft spot for the Yoshimura F1 bikes of the early nineties so im planning on building a bit of a replica with a view to race it at Olivers Mount and the Classic TT

 

 

I have started with a 1992 W frame and have a swingarm + linkage on the way as well as a K5 rear shock. The plan is to put a K2 750 front end on so i have a bottom yoke on the way. My research leads me to believe that the k2 bottom taper bearing will fit straight in and that I should just need a 32906 top bearing. Can anyone confirm or advise? I have also opted to use a triumph 675 rear wheel so if anyone who has done the swap could point me in the right direction that would be super. 

Pics on the way

Cheers 

Andy

 

Hey Andy,

where did you get to on the bodywork? So far I've only managed to find Airtech (USA, very expensive to ship from) and Ragged Edge (not taking bookings) who can provide it. You had any luck with other providers?

 

[Badger76]

On 11/28/2020 at 6:26 PM, BenedictIreland said:

Lovely, I am also building a replica of the same Suzuka bike! Gorgeous isn’t it? 

I'm picking up a 92 frame and swing arm in a couple of days to start my build also.

I'll post some pictures when I get started.

Really is a lovely bike....

[BenedictIreland]

How are those builds going? I got the forks into mine, and have all the various spacers and stuff made up to get the swinging arm in. Engine is back from engine builder, bodywork ordered...

[Kamikaze]

I think Spike is taking orders again, best check thou.

[BenedictIreland]

On 3/29/2021 at 6:28 PM, Kamikaze said:

I think Spike is taking orders again, best check thou.

He is! I managed to get an order in.. happy days!

[BenedictIreland]

Well, slowly the build is taking shape... from a dead frame and water-filled rather than water-cooled engine... we’re making progress

[Spazpecker]

I've been search for a WS swingarm, they're the braced ones all the cool cats use.

ive decided on a k4 as I have one in stock. Are you making it like a 750 RR? 

[BenedictIreland]

Little update... suspension in, brake discs on way, couple of spacers being made for rear wheel, but the rest of it is in. Lots of spacers and bearings and things replaced... engine will go in next week. It's got some nice red Samcos on it too!