Bigger Wheels on CB400f?

[crazypj]

A 2.50 rim on rear would be a much better idea than a 2.15 if you want to fit 130 tyre
I posted link and explanation of what it means
OP doesn't want to fit rims because it's too hard/too expensive but doesn't mind having tyres wear out 800~1,000 miles and bike being unstable
Whatever, ya can't fix stupid

 

[factive]

Hallelujah, about time we get a thoughtful discussion going with HELPFUL answers. Thank you guys. Seriously! Thank you!

Crazypj - I don't mind the work/expense.

How can I measure the current rims? There are no markings or stampings anywhere on the outside that indicates size. I am starting to believe they are not the stock rims. As previously mentioned, the front already has a 100 on there and the fit looks normal. The back has a 4.10. A quick measure with the tape on the back rim, it comes in at over 3inches, but surely I'm not measuring correctly.

I am probably going to get some new rims/spokes anyways. The rims are pretty pitted and have bad curb rash in some spots. Plus, I'd like to powdercoat/paint the inner part of the rim anyways.

As for Swivel-- dude you seem to have a major issue with people who have a different style or don't like the same things you do. Case in point:
http://www.dotheton.com/forum/index.php?topic=34464.msg375029#msg375029
http://www.dotheton.com/forum/index.php?topic=37668.msg409122#msg409122
http://www.dotheton.com/forum/index.php?topic=37668.msg409107#msg409107

Clearly you're incapable of contributing to this thread in a meaningful manner. Go wallow in your misery somewhere else.

 

[crazypj]

It's pretty rare that size isn't on there somewhere?
You can measure the outside and get an idea, this isn't exact sizing for Honda but works generic, may be about 1/8" off as Honda used slightly different profiles

 

[factive]

I found the size buried underneath rust/corrosion

rear - 185 x 18
front 160 x 18

Assume that translates into 1.85 & 1.60 which would mean they are stock rim size. Correct?

So I'm going to order some new rims & tires. This is what I have in mind.

rear: 2.15x 18 with 120/90 tire
front: 1.85x18 with 100/90 tire

Would I be better off going with 2.5 & 2.15 with same tire diams?

 

[crazypj]

If your determined to go with the bigger tyres go with the wider rims. (2.15 & 2.50)
Tyres will spread more and look/work better.
stick with 100/90 front and a 120/90 rear
It will cause enough tyre drag to slow bike down but it should also corner real well but you will find frame limitations pretty quick

 

[surffly]

He promised that he would never ride the bike hard enough to stress it so it's all good.
He has other bikes for that

 

[hillsy]

I found the size buried underneath rust/corrosion

You should probably get new rims in the appropriate size judging by this comment alone.

 

[ex119x]

Factive,
As long as you are going for wider rims and you want to run a 100 front and a 120 rear, go to the tire manufacturer's website and see what rim width they recommend. I know that Bridgestone has that info and so does Avon. I don't know about the others, but I imagine they do, also.
So do some research and get the right tires and rims. As I posted before, the 100 and the 120 will fit on the 400F with no modifications to the fender or chain guard, but they are close. And, you do need to run a front fender or fork brace because those 33mm fork tubes are flexy especially with that much tire.

Ken

 

[teazer]

Ken,

Thanks for the really useful and well written posts. It's a good reminder to the rest of us.

 

[eklimek]

Similar situation and found this old thread. The last comment suggested a fork brace. Any recommendations? Is there a thread dealing with fork braces?

Thanks

 

[neevo]

As long as you are going for wider rims and you want to run a 100 front and a 120 rear, go to the tire manufacturer's website and see what rim width they recommend. I know that Bridgestone has that info and so does Avon. I don't know about the others, but I imagine they do, also.
So do some research and get the right tires and rims.

I did this not long ago:

Ended up with a 2.15" rim up front and 2.75" in the rear. This was ideal width recommended for the tyre sizes above.

http://www.dotheton.com/forum/index.php?topic=31541.msg443367#msg443367

 

[o1marc]

A 2.50 rim on rear would be a much better idea than a 2.15 if you want to fit 130 tyre
I posted link and explanation of what it means
OP doesn't want to fit rims because it's too hard/too expensive but doesn't mind having tyres wear out 800~1,000 miles and bike being unstable
Whatever, ya can't fix stupid

I have recently learned that you can fix stupid, but it gets you 25 to life.