Topic: '04 R1 front swap to '75 CB550

[stereosilence]

Hi,

I have an opportunity to buy an '04 R1 complete front end for $350. I'm not sure how to tell if it will work or be "easy" or "difficult" to swap in. Any advice? If I need to be asking this,  should I just skip it altogether?

Thanks.

[Elan]

all balls bearings may have a bearing set for a direct swap in. They have a conversion chart on their site. But the stem height is also a factor. If that doesnt work, some people press in the 550 stem into the modern triple. Or machine a stem.  then theres getting a proper sized wheel, if you want spoked, look at the modern harley narrow glide wheels with dual rotors. Sportster fxt and such.  then 320mm non offset rotors redrilled to accomodate the harley wheel, then spacers for the 1" axle. and spacers for the calipers.

[matt mattison]

Fun Jimmy did this conversion. He did a pretty detailed thread on how it's done

[Franky]

FunJimmy did it with a R6 fork and it wasn't excactly a walk in the park Here's the thread:http://forums.sohc4.net/index.php?topic=27159.0

[FunJimmy]

Fun Jimmy did this conversion. He did a pretty detailed thread on how it's done

Thanks for the plug, but I used a 2001 R6 front end, but that being said, it's not the most difficult thing to do.
Get the seller to send you specifics re: stem diameter, length and fork offset.

Good luck
FJ

[matt mattison]

Fun Jimmy did this conversion. He did a pretty detailed thread on how it's done

Thanks for the plug, but I used a 2001 R6 front end, but that being said, it's not the most difficult thing to do.
Get the seller to send you specifics re: stem diameter, length and fork offset.

Good luck
FJ

For me, the biggest obsticle is the machining of parts. I don't have access to that stuff anymore. And there is nobody I trust to make up the parts.

[FunJimmy]

For me, the biggest obsticle is the machining of parts. I don't have access to that stuff anymore. And there is nobody I trust to make up the parts.

The parts aren't that difficult or technical.
Check out the local high school metal shop for students looking for a project to ace their grades.

[stereosilence]

Well, since my old front end was a POS, I had planned to drop an entire front end (wheel and all) in there. Those spoke wheels look like a PITA anyway.

Here is a problem I ran into:

(equation 1)
Trail=RSinø-0/cosø
R=tire radius
0=triple-clamp offset
ø=rake

According to Wikipedia, a tire website, and some forums, for the 2004 Yamaha R1,
Trail = 3.8" (wikipedia)
R = 11.9" (tire website based on wikipedia)
0 = 1.18" (forum)
ø= 24 deg (wikipedia)

Something here is wrong. For the equation to work, offset would have to be in the neighborhood of .95" (which seems low).

Then, of course, I haven't been able to find any stock numbers for trail and rake either. I plan to just drop it in, try to tune it up, ditch my rear lowering blocks, and hope for the best. It seems like a crap shoot and anything should be better than the gummed up front end that I had.

[matt mattison]

Well, since my old front end was a POS, I had planned to drop an entire front end (wheel and all) in there. Those spoke wheels look like a PITA anyway.

Here is a problem I ran into:

(equation 1)
Trail=RSinø-0/cosø
R=tire radius
0=triple-clamp offset
ø=rake

According to Wikipedia, a tire website, and some forums, for the 2004 Yamaha R1,
Trail = 3.8" (wikipedia)
R = 11.9" (tire website based on wikipedia)
0 = 1.18" (forum)
ø= 24 deg (wikipedia)

Something here is wrong. For the equation to work, offset would have to be in the neighborhood of .95" (which seems low).

Then, of course, I haven't been able to find any stock numbers for trail and rake either. I plan to just drop it in, try to tune it up, ditch my rear lowering blocks, and hope for the best. It seems like a crap shoot and anything should be better than the gummed up front end that I had.

Why not rebuild the current front end? New improved springs, seals,emulators etc. The engineering is already done for you. Would be easier, and perform better than new. I priced mine out this way recently, and it would cost about $400. However, the R6 front end should be a better set up no matter how much you dump into the stock forks.

[stereosilence]

Yeah, I pulled them off and they are nasty. I would have to spend a lot of time cleaning them and de-rusting (as well as $400 apparently). I have heard good things about the emulators though.

It looks like the R1 forks would go in pretty easy. Just drop in the all-balls and hook it up. I would also like the high performance brakes that would go with it. I'll be riding in Atlanta and that could make the difference one day. Plus, I like the look of the modern ones. But maybe I am deluding myself over the ease of their installation.

I thought FunJimmy just dropped the front end onto the bike with the allballs and added a custom cap somewhere. I thought most of the effort was trying to adapt a 3rd party wheel to the 2nd party forks...

[FunJimmy]

I thought FunJimmy just dropped the front end onto the bike with the allballs and added a custom cap somewhere. I thought most of the effort was trying to adapt a 3rd party wheel to the 2nd party forks...

Pretty much.
Most of the work was fabing up adapter plates and sourcing the rotor.
If you’re planning on using the supplied mag wheel and brakes it should be easy.

[stereosilence]

That's the idea. Not sure what the status is of the seller. He said he is busy (and apparently stressed) because he is going through court proceedings. Hopefully not for grand theft auto  .