Endurance/Racing Compenents

[Cibbersicks]

I suppose I'm aiming this at either the phase one guys, or possibly morepower or Millemille...

This may be a dumb question, but how do captive spacers work on 'racing' wheel systems? Are they atached to the fork/swingarm or are they attached to the wheel itself? Wat do they look like? Any pics?

Secondly, quick wheel change systems? How exactly do these work and what components are involved? I'd love to see the proccess close up and slowed down as I can't quite get my head around it, especially the honda system which has spring loaded calipers?

I'm just interested thats all...

Cheers

Tom

[Mark/Foggy]

All will become clear at Le Mans Tom. May even get to show you around.

Hang on a while and I'll get the photos together and I'll do some sort of explanation.

[Cibbersicks]

All will become clear at Le Mans Tom. May even get to show you around.

Hang on a while and I'll get the photos together and I'll do some sort of explanation.

*Waits patiently cross legged like a kiddy in a classroom*

Awesome

[levo]

Me too .....ooh shiney things and what does that do ................

[will#224]

The guy who did the zx7rr restoration showed loads of pics in detail on flick r. Buggered if i can find it though.

[guzzisti57]

I'm interested too . . . no more shambolic wheel changes at trackdays?

[will#224]

I found it. Maybe not the detail your looking for though

http://www.flickr.com/photos/22697976@N00/...57601582731693/

[Mark/Foggy]

Ok, making the wheel spacers captive. Imagine a tube that is an interference fit into the wheel bearings. If the tube then has a ring around it to stop it being pushed into the wheel when it's clamped up it's captive. So options are for either a fine tube or a decent diameter top hat. Everyone does it different. Repeat 6 or 8 times and make them all identical and that's that's the wheels sorted. Obviously the easiest way is to make a new smaller diameter wheel spindle, with a thread cut on one end and a nut and washer machined, as one, on the other end; saves finding wierd size bearings.

Now if we look carefully at this YART bike that Christian has helpfully taken to pieces we can see that 2 steel inserts have been clamped into the fork bottoms where the original diameter spindle would clamp up. On the left, as we look at it, the insert is a close tolerance, sliding fit. The new smaller spindle is gonna go in from this side. The other side insert is threaded internally.

What some teams do (Phase One) is machine a cup into these insets that will catch the outer diameter of the wheel spacers and hold the wheel just off the ground. As the wheel comes in from the front the calipers will be manually swung out around the tyre and back in again allowing the dics to feed into the caliper mouths. At the bottom of these Ohlins forks there are swivels that the mudgaurd mounts to, so that you don't have to remove the mudgaurd as you would have to on a standard set up.

If you want to get all complicated you get this popular setup below. The wheels for this setup will have large flat disc top hats that will catch on the lblades that point forward from the fork bottoms. As the wheel is fed in, it is guided along the top of these guides and the calipers automatically swing out and then back in again. Note that theses guides have a semicircular cut out in line with the wheel spindle so that when the wheel drops into these, the spindle can then be slid in and tightened up with an air gun.

All fine until it goes tit's up and one of the springs breaks or one of the little screws goes walk about. Keep it simple stoopid .

At the rear there are a couple of schools of thought, keep the rear sprocket on the wheel or leave it on the bike. Below we have solution 2. There's a great big bearing on the left hand side that the spindle is gonna come through and on the far side there is a captive nut that the spindle will tighten against. Permanently attatched to the wheel for the duration of the race (another to hat drifted in) is a spider male that engages this female shown. The spider has to rotated from the shown position and the wheel will go in and out vertically. Adjusting the chain on this setup is a little fraught in a wet race. Could go 24hrs on the right chain if it's dry though. Originally works Suzuki, has been adapted by many, think this is an ex-P1 set up, machined up by Spondon and living in an Alf's Kawasaki. You'll see other variations of the drive plate engagement, some good, some crap. Don't trust these myself, Russell could never get it to work reliably and I've seen too many other bikes out and about, where the spindle has gone walkies, not nice.

What I can't find at the moment is a photo of a 7 Stars Honda from the rear that shows exactly how wide the wheel hub needs to be. That wheel has to drop in vertically so the disc on the rhside needs to be 1/2 caliper width further out than the tyre edge so that it can drop down into the underslung caliper.

Here's the rear view of the P1 bike and you can just make out the sliding blocks on either side of the swingarm and where that caliper has to sit. You'll note that there are rails machined into these blocks so that the spacers can roll forward from the 1/2 circle cups that locate the wheel in the spindle position. This is approach 1, where the sprocket stays on the wheel and you have to push the wheel forward to get enough slack to unhook the chain. If it's good enough for P1 then it;s good enough for a works Honda.

Seven Stars again, note the chain adjuster blocks are quite tough. The white ring of nylon stops the chain dropping in amongst the sprocket bolts, easy to loose a finger here if the rider decides to leave while you're trying to get that chain back on the sprockets. He shouldn't, but riders have been known to get slightly revved up at say Suzuka

Final piece of the jigsaw is that captive sprocket nut. It has to be replaceable as alloy threads take a battering from the fast spinning, air driven spindle. Make one in steel and if it cross threads you may as well go home.

And finally hats off to Mr Yamaha-san for coming up with this. I'm at a loss as to how this works in practice, having never seen one race. If anybodies got one of these, can I come round and have a look pls. I really really need to know.

All photos stolen from the Endurance Racing Porn Thread You know who you are guys.

[ianthechep]

these really are works of art, nothing better than endurance bikes for motorcycle engineering porn....

[Cibbersicks]

Fantastic stuff Mark thankyou!

I've had to read that about 3 times to get my head around it, however don't get me wrong, what a cracking piece of work I appreciate the time you've taken!

It puts the standard system of fitting wheels to shame really doesn't it? Changing the rear wheels in my CBRs is a proper pain in the ass (The front is not so bad, apart from the calipers... and Honda recommending you change the bolts every wheel-swap)

It's such a struggle to fit everything in without the rear caliper dinking the wheel. You struggle to get the pads on the disc, you struggle to keep the carrier in place in the 'arm, you struggle to keep the evil spacers in the recesses in the wheel... all this whilst trying to hold up the wheel and tyre which seems to feel like it's getting heavier and heavier. I wish manufacturers would develop a better system for the masses.

I really like the sound of this captive spacer idea, as it would save a lot of arseing around, especially at trackdays. Also the chain adjusters that have a 'rail' to carry the spacers, holding the wheel in place such as this:

These would make the lives of trackdayers and general home-garage techies a lot easier when it comes to changing tyres.

[Mark/Foggy]

Given my fascination with the subject, I'm beginning to think that I'm touched in the head. Next week I'm gonna be working with #44 No Limits and for, hopefully, 24 Hrs I'll be doing it the hard way like all those owners of standard bikes.

What's worse it was my recommendation to run in the EWC as a SuperStocker Truth is that with the mass influx of serious teams and money into the Superbike class, along with more open regulations mean that the sport is gonna be money dominated this year.

Is that your work in Solid Modeller? May have so constrctive criticism if it's usefull

[DC98]

And finally hats off to Mr Yamaha-san for coming up with this. I'm at a loss as to how this works in practice, having never seen one race. If anybodies got one of these, can I come round and have a look pls. I really really need to know.

All photos stolen from the Endurance Racing Porn Thread You know who you are guys.

I'm sure I saw some close up pictures of this once and it confussed the hell out of me as the brake runs in the center of the sprocket, looked really strange but very cool.

[David W]

I've always been completely confused at to why bike manufacturers don't sell bikes with captive spacers and ramps on the swingarm to hold the wheel in place while you run the chain back over the sprocket. It can't be cost because there would be no more parts or machining once the tooling was in place, etc.

[speedy sie]

rear wheel holder can be made out of two hex bolts each sde and some 8mm tube to sleave the bolt,just top the bolt holes out,for the captive spacer to fitin to,then slide the spindle through,mine has it,and iv done it to my road sradblody simple and afetive.

all bikes sould ahve this done,and it would not cost that much at te factory to do this,so simple and worth the time to do.

[Inbred]

I was thinking of how the endurance boys did this so efficiently yesterday, whilst skinning knuckles and scratching rims trying to get the rear wheel of my K7 750 back in. I am sure the spacers where taking it turns to spring themselves across the floor.

Does anyone know where I can get hold of those cups/socket guides for the spindle nut? Racefit used to supply something for GSXR's but they were more of a make your bike pretty form than something functional, and about £60.

Ta.

[Devon]

I was thinking of how the endurance boys did this so efficiently yesterday, whilst skinning knuckles and scratching rims trying to get the rear wheel of my K7 750 back in. I am sure the spacers where taking it turns to spring themselves across the floor.

Does anyone know where I can get hold of those cups/socket guides for the spindle nut? Racefit used to supply something for GSXR's but they were more of a make your bike pretty form than something functional, and about £60.

Ta.

find someone handy on a lathe they should be able to knock you one up pretty easily

[phaseone_age]

Foggy forgot to say that you need to get swing arm widened by around 45mm at the axel and the disc is mounted out further than a stock wheel.

we have around 30 wheels 15 front and 15 rear.

The fronts have all been set up with disc spacing to within .25mm so as they fit in to forks with no resistance and so forks have virtualy no displacement when you do up spindle.

Oh and the poor wheel man has to make sure that all wheels fit both race bikes before we leave for a race and all rechecked again in race prep !

Oh was Le Mans on at the weekend or something ?????

1 super bike and a stocker ready for NW200

[Mark/Foggy]

The Superstocker that I was working on at the weekend had had new spacers made up. These were standard width, but oversize diameter. They'd then machined a journal ring in the outer circumference that allowed the original seal to seat and retain the spacers. Neat and relatively simple if not completely fool proof.