Topic: has anyone put a rear 750 comstar wheel on a 550?

[550cafeMN]

Im trying to do a 750 conversion to my '76 550. The wheels are from a '79 750F. Ive got the whole front end done, but now im on to the rear and in to some questions. To anyone whos done this before i have a few questions:

-i have the spacers from the 750 but due to the narrower 550 swingarm, i will have to mill them down to fit. Does anyone have the dimensions for spacers so that the wheel is centers

-once the wheel is centered, problems arry with the chain and sprocket. Do the two line up or do i have to machine down the hub for it to line up.

-the 550 chain doesnt fit on the 750 sprocket. What have people done in this situation

any answers to this would save me a lot of time and sweat. thanks, john

[Jeremy]

Hi John,

I have 78 750 comstars with disk brakes front and back on my 77 550k. I used the swingarm from the 750 so I didn't have to do any mods or spacers. I did have to machine down the hub so the sprockets line up and I used a 550 sprocket on the back(new)

[Matt at PSB]

The 77-78 CB750F rear Comstar will go right on if you re-use you existing sprocket carrier & spacers.

Matt at PSB

[550cafeMN]

thanks guys,

i thought of putting the 550 sprocket on to the 750 but the 550 has a 4 bolt pattern while the 750 is a 5 bolt pattern, how did you get around this? And how much of the hub did you have to machine down?

Also, i tried using the two 750 spacers but when i do there is only enough room for one of the chain adjusters, meaning i have to machine down one of the spacers to fit, but i am not sure which one should get it?

thanks, john