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Hi there, im new to posting on this forum but have been lurking around for over a year...!

I have a 2004 TBS fitted with TORS and K&N air filters, and im looking to make some more upgrades....I have the "green cams" that I will get round to fitting later this year but my main priority is changing the stock wheels over for something with less need maintenance (ie- ripping off the rust every fortnight...)

Ive seen some threads on here mentioning the use of speed 3 wheels etc but would like to know whats involved with changing over the wheels from stock; Can the original forks/spindles be retained or do they need work as well? How wide can I go on both the front and rear wheel?

Any help gratefully appreciated!
 

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Sorry, I don't have anything to add, but have been checking this thread regularly to see if anyone else does.

Anyone know what years/makes/models of mag wheels are compatible swaps with the TBS? Are different calipers required? Spacers?
 

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I'm in the process of fitting a set of T3 Daytona wheels to my TBird (which has a TBS front end and TBS rear wheel). My reason for changing the wheels is that I'm fed up with the hassle of fixing punctures on tubed tyres. It's all work in progress at the moment as my wheels are off to be powercoated so don't assume anything I am about to write is correct!

The rear wheel is a straightforward bolt up as the swing arm dimensions are the same across the T3 range. I did measure all the components/spacers for the rear wheel, but since they are the same as the TBS, I didn't note them down. In addition to a Daytona/Trophy/Sprint wheel, you'll need the early 'above the disk' type caliper and associated mounting hardware - such as caliper mounting, torque arm and naturally, the smaller brake disk to go with the wheel. I've tried a Daytona wheel fitted with a 180 x 55 tyre and there is sufficient chain clearance for that. I'm planning to go with a 170 x 60 though as that is more than enough for the TBird in my view.

The front wheel needs more work. The nominal sizes to which I've been working for the TBS front wheel (from right to left as seen when sitting on the bike) are: 35mm speedo drive + 12mm wheel bearing + 65mm inner spacer + 12mm wheel bearing + 21mm LHS spacer = 145mm between the forks.

The Daytona wheel uses the same wheel bearings, the only difference seems to be the length of the internal wheel spacer. The TBird's is 7mm shorter than the Daytona/Trophy etc. The Daytona inner spacer is 72mm so I've trimmed 7mm from the TBS LHS spacer and everything should line up. I've attached a pic of the front spacer with 7mm trimmed from it.

As far as I can work out from the part numbers, the 21mm LHS spacer is common across the whole T3 range, so the Daytonas etc. must have had different width on the triple clamps. What I haven't figured out yet is that the TBS calipers line up OK with the Daytona disks - the disk spacing on the Daytona wheel is exactly the same as the TBird Sport wheel at 140mm measured across the disk surfaces. I know the calipers themselves are different, but there must also be some differences on the Daytona fork leg caliper mounting points too. Although both the TBS and Daytona front wheels are nominally the same 17 x 3.5 size, the Daytona wheel is actually a touch narrower across the rim. Presumably, this will produce a slightly more curved profile to the tyre and may make the bike more keen to change direction?

The TBS caliper lower mounting bolts are fractionally too long to clear the rivets of the Daytona's floating type disks, but these bolts can be trimmed accordingly. Alternatively, the early type non-floating disks originally fitted to the Trophy range would probably be a straight fit to the TBS calipers.

Hope this helps - I'll post more when I've done a bit more work.
 

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The only thing I am curious about.. is the fact that you took 7mm (although I know it's not much) off the L/H, instead of 3.5mm and a corresponding 3.5mm shaved off the tach drive (assuming that is possible, I don't know). I am only saying this from an imaginary standpoint that the hub is equally 3.5mm wider to each side, rather than being wider, but offset 7mm to the left side, thus making the wheel centered doing as you have done.

I realize 3.5mm more to one side than the other isn't a whole lot, and maybe in reality it doesn't factor in much, as compared to the neccesity of the wheel being spaced solidly on the axle between the forks, without putting lateral expansion or compression on them, period.

This is interesting to me in the aspect that I have a TBS.. but more so generally because I have recently fitted '82 gpz750 forks to my '83 kz550, and it is an interesting journey, when using the stock wheel and trees, but different forks.
 

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All interesting stuff. I just bought a 98 TBS project. It has no wheels. So I'm in the planing stage for a wheel /fork swap. That being said I'm also looking for a TBS front wheel .Any leads please PM me. Nick
 

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Travster,

I don't have my Daytona wheel to hand at the moment as it's being powder coated. However, I did take some rim to fork measurements when I was fiddling around with the wheel. Fitting the Daytona wheel with the existing 35mm speedo drive puts it exactly in the middle of the fork with a 10.5mm gap from rim to forks at each side. Please bear in mind it's not the easiest thing to measure this distance with the nth degree of accuracy, but it looked close enough for my 'backyard bodger' skillset :)

Unfortunately, my TBS rim is less than pristine, so I could only take some approximate measurements and the TBS rim has a tyre fitted, so it made it a bit more awkward to check the distances. From what I could see, the TBS rim doesn't (or at least mine doesn't) sit exactly centred in the forks. The LHS gap was somewhere between 10-10.5mm and the RHS between 7-7.5mm. In the case of either the TBS or Daytona wheel, the disk rotors line up with the calipers so it looks like the speedo drive spacing is the critical factor. BUT - the part numbers for the speedo drives are different. The TBS shares the same part number as the 900 Sprint, but the Trophy and Daytona share a different part number. I've not had a chance yet to measure up a Daytona/Trophy speedo drive to confirm, but I'd be surprised if it is not 35mm.

BTW: The sizes I've mentioned up to now are all nominal - the LHS spacer actually measures more like 21.2mm (so I made the new one 14.2mm) and the 6005 front wheel bearings are quoted by suppliers as 12mm, but actually measure closer to 11.91mm. Once I've competed this project, I'll post what the true measurements are for my bike.

Please remember, this is still work in progress for me. Other members who have actually completed this conversion are in a better position to comment.
 

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From what I could see, the TBS rim doesn't (or at least mine doesn't) sit exactly centred in the forks. The LHS gap was somewhere between 10-10.5mm and the RHS between 7-7.5mm.

I've heard that comment before.

My original wheel has the rim centered between the forks.
I have examined a 2004 TBS carefully, and measured with calipers. It also has the Rim centered between the forks.

I have a spare TBS wheel, and it is not centered between the forks.

Based on my limited observations I think my spare wheel needs to have that corrected. And I plan to have that done soon.
 

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Just thought I'd throw in 2ct here....

I have Tony Foale's book 'Motorcycle Handling & Chassis Design' &, tho' I don't pretend to have followed every technical detail to his level of understanding, I have to conclude that the wheels must be in as perfect alignment with the bike centre line as possible, & at least with each other.

This is especially true for the front wheel as even a small offset either way would alter the effective trail one side to the other & the forces thus applied.

As only the tiniest angles of countersteer intitiate relatively large steering movements, even small amounts of play or geometry differences can lead to very inconsistent behaviour. (This is one of the most difficult areas for alternative (eg. non-fork lever type) front end designs where steering is acheived indirectly via links.)

Note also that motorcycles do not actually travel in a straight line - ever. What we think of as straight travel is in fact a series of self-correcting 'arcs' along the road.

It seems inconceivable that front wheel or steering yoke offsets sideways could be in any way desireable.

The front wheel rim on my Legend is (thankfully :D) dead centre of the legs, as best as I can measure it.

Mike
 

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I have to conclude that the wheels must be in as perfect alignment with the bike centre line as possible, & at least with each other.
Not the centerline of the bike, but the center line of gravity which may lie off to one side or other of the centerline of the bike itself - you will notice that on the T3 classics there is a small offset - I dont recall exactly to which side but I think it is to the right.

Yes you REALLY must have the wheels in alignment or weird handling characteristics can occur. This is my main worry with people swapping to other wheels or forks on here - I worry that they might not know about checking this
 

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Mike / Mick,

Thanks for the feedback. I couldn't understand why the disk rotors line up just fine with the calipers, yet my TBS rim appears to be slightly offset. I know that some (usually rear) wheels are dished to keep everything lined up, but I expected the front to be smack in the middle of the forks - as is the Daytona wheel I checked. The spokes on my TBS wheel are all straight/tight, so this rim may been been built slightly out of alignment from day 1. I'm going to check my old 18" TBird wheel which only has a couple of thousand miles on it to see if that is centred correctly in the forks.

I can't say that I've ever noticed any strange handling or unusual tyre wear - which means either that:
A) I have enough raw ability to ride round any problems
B) I'm too dumb to notice

For the moment, I'm going with option B - :D
 
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