Rear wheel/spindle

[Bitza]

Hi all, OK my latest issue is to do with my rear wheel & spindle. The bike is based on a 1994 machine with the original 17mm spindle, I have been using a 4.5" rear wheel but with my next round of mods I'm going to a 5.5". I've got one off a 2003 ST2 but the bearings & the internal spacer tube, is obviously for a larger diameter spindle, what can I do to make it fit my 17mm set up?

[Mr Gazza]

Funnily enough I have been mulling over how to make a wheel with a 25mm hollow spindle, work with a 17mm axle.
First call would be to look for bearings with the same outer diameter and a 17mm inner diameter. The easiest way to do that is to take one of each bearings from both types of wheel and spend a little time leaning against the counter in the bearing shop.
Failing that being a success, I would look into getting bushes turned up to be an interference fit, inside of the larger bearings to reduce them down to 17mm.
It is most important that the assembly clamps up the inner races as per normal with whatever size spindle, so the 17mm spacer must be used.

If bushes are used to reduce the inner race diameter then I think that a thicker wall spacer tube should be made to bear on both the inner races and the bushes. Except of course there might not be any actual clamping force on the outside of the inner races in that case, unless adaptions are made to whatever contacts them normally. (tricky in my case as I have the floating calliper.)

One bonus of using a later wheel might be the availability of polyurethane cush drive inserts?

My reasoning that the inner races must be clamped, is that the wheel could slip sideways off any bushing applied to the inner races, if only the bushes are clamped.

...Just realised that I have made a Utopian type post and should end with a note, something like; I've no personal experience of this and am unfamiliar with the 25mm spindle set up... must make another pot of tea.. ect.. ect..

[Dukedesmo]

Originally Posted by Bitza

I've got one off a 2003 ST2 but the bearings & the internal spacer tube, is obviously for a larger diameter spindle, what can I do to make it fit my 17mm set up?

You need bearings with a smaller ID and the correct 17mm spacer to sit between them.

I think they are 6303-2RS which have a 17mm ID rather than 6005-2RS with a 25mm ID but check the width of the existing bearing/spacer combination as there maybe some differences (6303 is 14mm thick and some bearings are only 12mm thick).

[Bitza]

Well thanks guys, as usual I'm highly impresssed with the knowledge that's out there and the response time, are you just waiting to solve my problems? if so I have this rather hefty debt.... thanks for the help, Bitza.

Originally Posted by Mr Gazza

Funnily enough I have been mulling over how to make a wheel with a 25mm hollow spindle, work with a 17mm axle.

Front or back wheel? I have a 17mm front wheel spacer going spare if it’s any use? Direct replacement of the 25mm one, then it’s just to replace the bearings (and any spacers or speedo drive dependant on the model) Also currently got the axle for sale on ebay, but guessing you have one already.

Sorry for the thread hi-jack @bitza

[Zimbo]

Just have a quick check to make sure the wheel spoke shapes match, if that would be something that you are concerned about. The early wheels have spokes that are narrow at the hub and wide at the rim, the later ones are the other way around.

[Mr Gazza]

Originally Posted by on-yer-bike

Front or back wheel? I have a 17mm front wheel spacer going spare if it’s any use?

Thank you for the offer fella.. I already have a 25mm front axle set up. The conversion project for the rear, is only in my head. In case a certain set of wheels happen to come up for sale.

Thanks Dukedesmo for the info and saying so much with so few words.

[Bitza]

OK so have done a bit more research re; bearings to fit the later wheel (25mm spindle) and an earlier 17mm spindle set up. I haven't found any standard bearings to suit, but have found a specialist type which I think should do the job. The size is 17x47x12 (inner dia x outer dia x width), the bearing is a sealed cam roller ball bearing with cylindrical outer. These bearing are designed to be used as rollers, where the inner race is fixed to the device and the outside of the outer race is utilised as the track roller, so the outer race is beefed up/thickened to take the wear & additional forces of being a roller. However I have been assured that there is no reason why they cannot be used as a standard bearing. However there are two types of these one of which has a radiused outer referred to as "crowned" (to make it a more practical roller) which you do NOT want, the other form has straight cross-section which is one to get. Most of this type of bearing seem to be coming out of China, but I have found an alternative supplier INA (part of a goup that includes FAG which I have heard of), their number for the bearing is LR203 and I've been quoted around £18 inc vat.

So hopefully by sleeving down the original 25mm inner spacer to 17mm I should be in business, mind you as I'm writing this have just thought that I had better check the widths of the two types of wheel. Just when I thought I had cracked it too. Bitza

[Bitza]

Bad news, the 2003 ST2 rear wheel (25mm spindle) hub is approx 6mm wider, on the sprocket side so I'm at a loss to see how I can make it fit my 1994 frame/swinging arm, so has anybody got a spare 2001 type (17mm spindle) 5.5" three spoke rear wheel (with spoke getting smaller towards the rim), and of course is anybody looking for a ST2 wheel in grey?

[Nasher]

I've put a pair of ST2 wheels in my 900SS mongrel project and had exactly the same issues.
The standard SS wheels, spacers etc are the same as the standard Monster parts so the same resolutions apply.

After changing the bearings for ones of the right combination of inner and outer diameter I reduced the overall width by skimming a few mm off the sprocket carrier etc in my lathe.

Because I couldn't get bearings in the correct combination of ID, OD, and width, I ended up with wider ones and cut the bearing pockets in the wheels deeper in a mill. Unfortunately my mill is too small to take the wheel so I had to borrow one at a friends business. Of course I also had to make up a new smaller ID and shorter bearing spacer tubes for inside the wheel hubs.

I seem to remember I gained a couple of mm by reducing the length of the spacer between the wheel bearing and sprocket carrier bearing, taking up most of the gap that was between the sprocket carrier and wheel, then the rest came off the outer spacer and a little off the outer face of the carrier to get a gap back.
Chain alignment was put right by skimming a couple of mm off the face the sprocket bolts to.

As you can see, both ST2 Wheels are in:





Nasher

[Mossleymonster]

Nice Bench

[Nasher]

Originally Posted by Mossleymonster

Nice Bench

Thanks.

I spent too many years bent double over bikes to attempt another full build without some way of lifting it up to a better height.

The advantage over a lifting bench for a long term build is the storage space underneath.
Plus of course at @£40 for the materials including HD Castors, you are not tying up an expensive lifting bench for the duration.

Nasher

[Jez900ie]

Originally Posted by Nasher

Thanks.

I spent too many years bent double over bikes to attempt another full build without some way of lifting it up to a better height.

The advantage over a lifting bench for a long term build is the storage space underneath.
Plus of course at @£40 for the materials including HD Castors, you are not tying up an expensive lifting bench for the duration.

Nasher

ts a nice bench, all the better for being inexpensive, replete with storage
The solution to the wheel fitment is clever, and satisfying to achieve yourself
The bike is cool

[Nasher]

Thanks Jez900ie

In case anyone is thinking of building a similar bench, it's worth pointing out that it's heavily over-engineered for strength and safety with 3 longitudinal beams top and bottom.
In addition I put a central bulkhead in the two end quarters to stop any chance of it folding flat.



Nasher

[Bitza]

Haven't been able to find anyone willing to take on re-machining the 25mm spindle wheel into the 17mm format, so have found myself a wheel of a 2001 900ie Monster, which is plainly what I should have done in the first place, well next time?! Bitza.