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Discussion Starter · #1 · (Edited)
Here's my conversion I'm slowly gathering parts for. I'm putting on CBR 954 USD forks with an RC51 SP1 front wheel to match the 6 spoke design of the 250. Don't have all the parts yet, still waiting on the front wheel to come in the mail but got board on a rainy day and decided to do a test fit.

The front triples have their differences but share dimensions in the critical areas. The bearings are identical, as is all dimensions of the steering stem. All the nuts and seals are also the same. Only major differences are their physical size and the offset. The 954 is a lot less offset and causes some minor clearance issues.

Along with the better damping and adjustability, come the massive 330mm rotors and 4pot callipers. The brakes I got also came with stainless lines as an added bonus.

Triples Comparison...


I was surprised at their weight difference too.

250... 1.919kg


954... 1.927kg



Next I measured fork lengths. They are nearly identical, right down to the position of the retaining ring at the top.

Fork Comparison...






And their minor difference in weight...

250... 2.971kg


954... 3.325kg

Next came a test fit of the Triples.





Ignition fits in perfectly



Only clearance issue is the angle for the ignition. Easy fixed by grinding the angle off the frame.






Then the forks went in.






Clearance problems.



Not quite full lock. Not a major issue as I'll just add a cap screw to the stopper to limit lock.




I didn't try the front bodywork with the forks yet, but image it'll require a little trimming because the 954 forks are a fare bit wider.

While I had the scale out I figured I'd measure a few other parts just out of curiosity.

Top Assembly of Bearing, Nuts, Seal... 0.207kg


250 Axle and Nut... .352kg


954 Axle and Nut... 0.473kg

That's it for now, until parts come in I put the bike back together so I can continue to ride until the snow falls. I also will be rebuilding the 954 forks with new seals, guides and oil. One of the forks is leaking so it needs to be done.
 

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top work! will be very interesting to hear feedback on how it rides and stops.
 

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What's the compression on the 954 forks like compared to the 250's? I'd be worried about upsetting the suspension balance too much, obviously the 954 is a lot heavier than the 250... Not a problem if you're getting them resprung and revalved though, I guess!
 

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Discussion Starter · #7 ·
What's the compression on the 954 forks like compared to the 250's? I'd be worried about upsetting the suspension balance too much, obviously the 954 is a lot heavier than the 250... Not a problem if you're getting them resprung and revalved though, I guess!
Well I've already replaced the rear suspension with a fully adjustable Penske racing unit with 600lbs spring so the front was already too soft. BUT, right now the 954 is softer than the 250 because all the adjustment are set full soft. That's the beauty of adjustable suspension. I can make it whatever I want.
 

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this is exactly the kind of overkill that I applaud!

Well fuckin done! Look forward to the finished result!

PS. Wish your fuckin scales were metric!
 

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Discussion Starter · #9 ·
Haha, it has a unit button on it to make the switch but I'll edit my original post with the conversion to Kg
 

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Well I've already replaced the rear suspension with a fully adjustable Penske racing unit with 600lbs spring so the front was already too soft. BUT, right now the 954 is softer than the 250 because all the adjustment are set full soft. That's the beauty of adjustable suspension. I can make it whatever I want.
After market springs are not available?
Of course they are, post was in reply to the adjustment comment, that's all.
 

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Discussion Starter · #15 ·
Isn't canada metric? they cant be as backwards as the yanks.
Yeah but I count the weight of the bike in lbs so it's easier to calculate it that way. I'm quite familiar with both metric and imperial.

And as for spring rates for the front forks, it is sprung for a bike that weighs over 100 pounds more than the 250, so the balance should be pretty good.
 

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Discussion Starter · #16 ·
I got a 2012 CBR 1000RR front fender for my 954 front end yesterday. Fitment is pretty damn close, though I think the 2012 forks are a bit narrower but the fender is a brand new take off of a guys bike that replaced it with carbon. The inside was as clean as the outside.





There's just enough clearance that the forks don't hit as they move up and down.








The rear is a lot narrower. Nothing a longer bolt and a few washers can't fix though.





The front fitment is maybe ¼" wider than the fender, but it fits fine.




 

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good work mate, love the detailed pics.

I think you should also do a 954 fairing conversion?? =)
 

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Discussion Starter · #18 ·
That's a bit more than I want to do. Plus my fairings look really good in all Repsol paint. Just have to paint the new rim and fender to match.


Sent from my iPod Touch
 
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