USD forks onto CBX - Please advise

[djpauw]

OK so as part of my intended CBX build-up I also want to put some nice newer technology upside down forks on the bike. I have seen pics of (amongst others) +- '04 model CBR front-ends, +- '98 GSXR front-ends etc.

Logically it is fairly obvious to me that the main concern in such a conversion will be that there may/will be differences in the diameter and length of the stem.

So my question to you is this: Is there a known combination of parts that work well or even ideally? Is it perhaps known that the stock CBX stem's splines (or whatever you call it) matches perfectly onto a specific newer model's triple clamp? Maybe there are different neck bearings to be used with a different stem...? I'm hitting around in the air here, but I hope you understand my question.

Perhaps someone can reply with as much detail as possible on their own conversion with detailed pics? Or supply a link to a thread I may have overlooked?

Thanks guys!

[EMS]

You can press the original CBX stem into a different, suitable triple lower. Many people have done that. A major concern when using modern USD forks is the shorter overall length which lowers the front end, and thus changes the steering geometry and reduces ground clearance.
As it seems that I may have plenty of time to work on elaborate projects in the near future, I am contemplating putting a chassis together with parts I have collected over time. I am just now returning from Germany where I was able to come into detailed pictures and plans of a frame that Mike Hailwood had intended to use in a 500cc Honda racer. It was build by Reynolds. I will use this as a model for a custom frame. I will base it on a stock CBX frame by retaining the steering head in order to make registration easier and keep the CBX model name. I will change the rake slightly to adapt to a Ducati Multistrada USD front end, which has longer fork legs than one of the common repli racer forks. The bike will also NOT have a single sided swingarm, but stereo shocks and will not have Ducati tail, because it will be a classic line two-seater.
Stay tuned.

[djpauw]

You can press the original CBX stem into a different, suitable triple lower. Many people have done that.

Good to know. Now if someone could just tell me WHICH ones are "suitable" to accept the CBX stem......?

A major concern when using modern USD forks is the shorter overall length which lowers the front end, and thus changes the steering geometry and reduces ground clearance.

Thanks and yes I am very aware that such mods changes the game completely. Maybe again something about my personality but I love having something to tinker with and this bike will certainly fall in that criteria. It is very likely going to take me years to finetune the suspension to where I want/need it, but there is a lot of enjoyment to be had along the way. For the record I am not too concerned about ground clearance as I don't intend driving up and down curbs or stairs. Geometry may be more what I need to focus on as the bike should behave properly...

So anyone else have advice on suitable triples and forks etc??

[Rick Pope]

[quote="djpauw For the record I am not too concerned about ground clearance as I don't intend driving up and down curbs or stairs. Geometry may be more what I need to focus on as the bike should behave properly...
[/quote]

I suggest you pay attention to ground clearance if you want to go around corners. A wide engine needs considerable clearance to keep from making a mess of the cases.

[djpauw]

Thanks for the general advice so far, but I must admit I am somewhat disappointed that no-one who has done something like this have posted a reply yet... No pics, no detail info...

[steve murdoch icoa #5322]

Any info you need on customizing your CBX including usd forks can be found in the build by Mike.
viewtopic.php?f=102&t=7330&hilit=diamond

[daves79x]

A little info for you - Steve's link, which you've already seen, I think, is the best by far you'll find here, or anywhere on the web. The other guy we've referred to is not on the forum, but has done many such conversions. Frankly, it makes for good discussion, but the majority of us here don't prefer to modify our CBX's to nearly that extent. And you'll have to be patient with this bunch - we are, for the most part, old, cranky and move a lot more slowly than we used to with our projects. In summary, what you read about Bikeymikey's custom build will be about the very best info available here.

Dave