73 honda cb500-4 tire size

[madness69]

Whats the bikes rear tire I can put on my cb500-4 with out modifying the bike except for taking off the chain guard???

[bitzz]

The stock sizes would be 90 front and 100 rear.

[madness69]

what I mean is what the biggest rear tire I can put on without modifying

[inreb]

Do you have a manual? Search the rim width. After that it will be easy to figger out.

[bitzz]

what I mean is what the biggest rear tire I can put on without modifying

UHmmmmmmm
You have the bike, there in front of you.
We are out here in internet land.

...maybe if you held your computer closer to the bike....

The rear rim a WM2= 1.85" wide.
You can put a bigger tire than a 100 on it but will wear weird and do you no good.

You can put a 100 on the front with the same results.

Why do you want wider than stock tires on THAT bike. Have you never ridden it? You don't need tires, you need to get rid of the hinge just behind the fuel tank.
Big tire will make it worse.

[inreb]

It's madness

Maybe a wider tire with more aspect ratio?

[RetroGrouch]

110 front and 120 rear… grasshopper.

[Gryphon]

110 front and 120 rear… grasshopper.

Close...
110 front would be technically too big.
A 110 front is a huge (litre-class) front tire.
100/90 front, plus 120/80 rear would be as big as you should go.
Back in the 70's the Dunlop K81 (TT100) was the tire to have...
The popular rear size was 4.25/85-18.
120/80 is the closest modern equivalent in (metric sizes).
Regards

[inreb]

Close...
110 front would be technically too big.
A 110 front is a huge (litre-class) front tire.
100/90 front, plus 120/80 rear would be as big as you should go.

I'm running a 110/80/18 on the front @2.5 rim which is recommended

The OP's 1.85 rear rim should not carry a 120/80. Just 'cause you can squeeze it on don't make it right.....

[bitzz]

He could run the Avon Super Venom 650 tire. A full 6.5 inches wide, with a cantilever sidewall, made to fit a WM3... BUT it will be awful!

That bike squirms, shakes and shimmies with OEM sized bias ply tires, OH and the swing arm flexes like cooked spaghetti.

Again, why are we talking about putting modern sticky tires on a 40 year old bike?
It just don't work!
I know several people that run that bike in Vintage classes... slap an 18" hoop on the front with a 100, a 110 rear and that's as good as it gets until you start modifying the frame. Box the upper hoop to the swing arm pivot, strengthen the steering head, AND GET SOME REAL SHOCKS, before you will see anything like handling in a corner.
That bike will start DRAGGING stuff WAY before you start to use the tires.
I've been racing the 450/500 twin of the same vintage (same wheels) for 20 years. Mine has EXTENSIVE frame mods, and 100 front and 120 or 130 rear (depending on which track).

[RetroGrouch]

Close...
110 front would be technically too big.
A 110 front is a huge (litre-class) front tire.
100/90 front, plus 120/80 rear would be as big as you should go.
Back in the 70's the Dunlop K81 (TT100) was the tire to have...
The popular rear size was 4.25/85-18.
120/80 is the closest modern equivalent in (metric sizes).
Regards

OP never asked what was practical or even safe. I merely provided the answer to his question. I know 110/90 front and 120/90 rear in 18" Bridgestone Spitfires fit old Hondas because I've done it.

[madness69]

Thanks for all the responses. I actually don't have the bike yet to look. Its still in my buddy's garage until I get it safety'd this weekend. I dont want to put anything ridiculous or unsafe on it. If its 90 ill go 100,If its a 100 ill go 110. I also did ride the bike last year and loved it. Thats why I bought it when i became available. Anyhow here's the best picture I have at the moment.To me It looks like both tires r the same size..... I was also wondering about the dynatek ds1-2 electronic ignition. As much as I would also would like to buy the dyna coils,is it neccesary?? Should the stock coils be good enough as long as there in good shape????