Triumph Rat Motorcycle Forums banner

F3 Wheel/fork swap

51K views 139 replies 19 participants last post by  Actionabe 
#1 ·
I am in the process of getting started swapping onto my thruxton cbr f3 wheels and forks.The reasons being I really would like to have better brakes, tire selection and it kind of looks cool. Since my thruxton has the electronic speedo I am hoping to do this swap with the minimal amount of changes besides the forks,wheels, clip-ons and mirrors. I also want to be being able to swap back if I want to so all the bearings/ spacers will be new parts.

I have been searching the forum a lot and trying to glean all the information on this project, there seems to be a lack of pictures so as I do this I am going to try and take a bunch to document it. Also if anyone who has done this sees me going off in the wrong direction would appreciate a heads up..

So far I have accumulated all the parts I need besides the clip-ons, mirrors, front axle and brake rotors. I have torn down the forks,painted the lowers and replaced all the bushings and seals. I just got the f3 cush drive machined and the thruxton spacer as well. The next step will be getting the rims powder coated. I attached a before picture, pictures of the forks torn apart and rebuilt and before and after pictures of the cush drive bearings and spacers. The triumph one is the darker colored spacer.
 

Attachments

See less See more
5
#34 ·
I think that is what kind of inspired me to do this, love the look of the Norton but not the cost or reliability issues. That and the 2010 675 black and gold.


I'm pretty sure I know most of the answers but what stuff did you end up machining? Do you have the specs? I am looking at doing a F2 wheel in the rear and F3 front.
So far the cushdrive, cushdrive spacer and a new rear wheel bearing axle spacer. I dont have any specs but I could measure some of the stuff. I just brought the machinist the triumph bearing and he bored out the cushdrive to match, turned down the spacer to match the f3 spacer and then he made a rear axle spacer with the length of the F3 one and the inside diameter of the thruxton spacer. The rear wheel is definatly off center so more work is going to be needed once I get out there and start the alignment. The rear looks to be off at least 1/4" by eyeballing it. So minumum going to have to machine the wheel spacers, shim the rotor and turn down the face of the cush drive and probably shorten the sprocket mounting studs. Pieman mentioned he needed to do this in the other thread on the F3 swap and to line it up perfect it will be required. Not looking forward to it, going to be alot of measuring and measuring again...

Nice job!
Thanks! Just wish I could ride..Another 8in of snow yesterday.
 
#35 ·
Started messing around with the alignment tonight using the string method. The first time I used yarn and the difference I got was 30mm but there is no way to move the wheel 15mm. So I put the bike on the race stand to get it closer to level and also adjusted the wheel to be a little off from the factory rear wheel adjustment marks. This got the differential down to 10mm with the wheel tracking straight within 1mm. It is possible to move the wheel that much by shaving down the cush drive face and also shortening the sprocket studs.
Next I tried fishing line to be more precise and the offset was between 15-20mm. Just by eyeballing and measuring I believe for perfect alignment I would need to move the Wheel to the right by 5-10 mm. With all the variables in the string alignment method I just am not confident I can get a solid number. I don't have the experience but does anyone know if an offset like this will effect handling much? would it be worth it to do the machining for this? How does your bike handle Rich? Any bias to either side or drift? Wish I could test ride but single digits tonight.. need to have her ready for the riding season, no time for maint then.
I attached a few pictures so if anyone sees me doing something wrong in the alignment let me know! Thanks!
 

Attachments

#38 ·
I don't have the experience but does anyone know if an offset like this will effect handling much? would it be worth it to do the machining for this? How does your bike handle Rich? Any bias to either side or drift? Wish I could test ride but single digits tonight.. need to have her ready for the riding season, no time for maint then.
I didn't notice any adverse handling caused by the ~1/4" offset to the left on my rear wheel. I've only run my machine about 100 miles since fitting the rear wheel...Easy13 (eric) can probably give you a more complete response since he's had his wheel set in place since August and has racked up several thousand miles.

In my case, the rear caliper seems to align well with the rotor and the rear sprocket alignment is possibly between 1mm and 2mm off, with the offset being to the left of center. At this stage of the game, I'm not worried about the wheel being off center a hair since it doesn't seem to cause any handling issues. I would, however, like to resolve the sprocket alignment issue. This gives me the option of either shimming the rotor 1.5 mm to the left & moving the wheel to the right by fabbing up a 1.5 mm thicker left hand spacer OR leaving the rotor be and shimming the drive sprocket 1.5 mm to the right. The first option is more complex, but removes some of the wheel off-set...the latter is easier, but leaves the wheel where it is currently is. I suppose there is also Option C - which is the 'no action alternative'...ride it and see if the sprocket wears funny.

Good luck,

--Rich
 
#41 ·
A few questions on that, sorry for being so confused..Wish I had my own lathe so I could experiment.. The 7mm you took off the cush drive, did you also machine down the mounting surface for the sprocket at all? It looks like if I shortened the studs 7mm they only would thread into the nuts a little ways. When you did the other spacers did you overall shift the wheel right 7mm? Do you see any problem not running the dust seal in the cushdrive? Thanks for the info!
 
#42 ·
The sprocket studs were removed and then 7mm taken off the face so it didn't hit the swinging arm. You may well be right about the studs, it was a long time ago. They did need shortening to miss the swinging arm, but I may have taken them down to the height of the nuts.

No problems with not running a dust seal as I had the wheel spacer on that side made so it was just smaller in diameter than the dust seal so it runs in the cush drive casting and keeps enough dust out. It's not as good as a seal, but almost three years in and the bearing is fine.
 
#44 ·
Just got back from the machinist and hopefully once I get everything installed sometime this weekend the rear wheel will be in better alignment. Took .3" from the face of the cush drive and added and subtracted the same from the appropriate spacers. Also had some spacers made for the rear disk brake. .2" was removed from the sprocket mounting face and the studs were turned down.
 

Attachments

#45 ·
Looking good. On the rotor side, were you successful in finding longer shoulder bolts? If so, do you have a source?

I'm still thinking that I'll live will a little mis-alignment to the left, but it would be great to get the sprockets perfectly aligned via moving the wheel about 0.060" to the right...

Cheers,

--Rich
 
#47 ·
it's easier to shim the caliper over to align with the rotor....


Mike,

That occurred to me but was fixated on the four small spacers in Actionabe's picture and went on a mental tangent.

In my case, I am waiting for TTP to fabricate an offset, over-the-top caliper bracket for F3 rear wheel applications! :)

Cheers,

--Rich
 
#48 ·
I had those spacers made but I have not had any luck with finding longer bolts yet. Probably will end up trying to do something on the caliper side but I have not messed with it yet I just had them made while I was at it kind of a back up plan...If you only need .06" spacers the f3 rotor bolts may be long enough to work..
 
#50 ·
All installed, looks like everything is falling into place. I used the spacers I had for the rotor on the caliper mount bolts to move it over. attached some pictures. Everything looks really close. The chain alignment looks pretty good, a little close to the tire but I still have about 2 mm clearance.
 

Attachments

#51 ·
Well got tired of waiting for help making the front fender brackets and spent a few hours out in the garage bending sheet metal. I am not finished grinding them and cleaning them up but this is what I have so far. The radius of the fender is off from the wheel because of the rim change but I cant make up my mind if it is enough to justify getting a custom front fender. What do you guys think?
 

Attachments

#54 ·
The radius of the fender is off from the wheel because of the rim change but I cant make up my mind if it is enough to justify getting a custom front fender. What do you guys think?
I think the fender looks like its floating a bit too high over the tire...any more clearance beneath the mount to lower it more?

Does triumph use the same fender on the mag wheel bonnies as the thruxton? Just wondering if there is a curvature difference or if they are they just using the 18" wheel sport fender on the 17" mag wheels...

Regards,

--Rich
 
#55 ·
I could lower the fender a little more but then it seems to aggravate the radius difference. I was trying to avoid the sports bike fender just because it seems to be the tip a front end swap has happened. Although after seeing piemans, the f3 fender looks a lot better than I thought it would . .

I checked the fender part number for the mag wheel Bonneville and it is a different part number from the Thruxton so that may be a good option. I kind of hate to pay that much just to modify a new part so it would be nice to find one on ebay.. Air tech has a generic vintage looking 17in front fender they designed to fit sports bike swaps so that is another option, but after paint it would probably be the same as if I got the mag wheel fender.... Will probably throw the thruxton fender back on until I can decide...decisions decisions..
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top