I'm starting a Cafe/whatever cb750 project. I want to go as wide as possible (140 maybe) in the rear . What size will fit without rubbing the chain?

Heres some pics of the bike during disassembly.

 

I'm using a 150/80/16 with a 16" harley rim on my CB750 - probably room for more, if I went with a wider wheel. Since you have a '78 you already have the longer/wider swingarm.

 

Nice bike! More pics please. Everyone that I see is running a 140 but I wanna go wider. That 150 looks good on your bike.

 

Whats the stock rim size? The 150 is a little pinched on my bike... Excel makes a ton of rims in whatever size you need, too. I think if I had to do it again I would've gone with 17" rims, more modern rubber and had this shop do the building/truing: http://store.eastcoastwheels.com/

 

Stock rim is 3.25 front/4.5 rear . I was thinking about running a 110/80/19 in the front and a 140/70/17 in the rear. Does that sound right?

 

btw how much was that chain? Looks good.

 

Is that the stock exhaust? You definitely want to hang on to that.

 

Yeah its stock, but its rusted out.

 

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You sure? I'm pretty sure they're quite a bit narrower than that.

 

Actually now that you mention it . I think I misread the manual I have. Does a 2.5 rear wheel sound right?

 

Maybe, but there's so many different sizes through the years on those old honda CB's. It may be stamped on the rim somewhere too but I'm not sure.

 

Was it difficult to fit the Harley Rims on your CB?

 

All you need is a 16" drop center rim with 40 holes and a spoke kit. Then you just lace the spokes, install new tire and go.

 

Thanks a lot! Do you know where I can find a front wheel that will fit my 1978 cb 750 that has dual discs on the front. Im having trouble finding a dual disc front spoked wheel?

 

Sure, an early GL1000. I believe 75-77 were spokes, but I could be wrong. I do know for sure that 75 and 76 were spoke rims. Easiest thing to do is swap the entire front fork set up.

 

The tire size on the 750 isnt too bad, but if you go any bigger than a 140 they tend to get higher as they get squashed in the rim.
Plus, when the bike goes into a corner, the frame will flex slightly and you may get the tire rubbing on the shock spring.
I have built one or two of these machines and have had a few of these issues before.





I prefer the 130 to be honest.
But thats entirely your own taste my friend.



Peace and Grease

CARPY

 

I have a stock 72 CB750 K2 what is a larger tire that I can fit with out sacrifice of performance on the stock rims...I heard a dunlop gt501 120-90-18 or 130-80-18 does that sound right?

thanx for the sugestions