Your “two cents” on wheel/rim size

[Bewarethemoon]

Hi guys, as the title states I’m after your thoughts on ideal rim size for my build.

I’m going to lace up some hubs I have on order and I’m pondering the unknown (to me at least) of rim size to fit my need.

I’m really wanting to use 18” rims but insure of what rim size to go with.

I’m upgrading shocks to Ohilns, using the swingarm from a TX750 and forks off a 1999 R6 (YZF). I plan on doing a little bit of track day riding so trying to get things set up right.

Any advice would be hugely appreciated!

Cheers. Daniel.

 

[TwoManyXS1Bs]

Looking for rim/tire sizing compatibility charts?

 

[Bewarethemoon]

Looking for rim/tire sizing compatibility charts?

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More like ideal rim widths. So for the front 1.85, 2.15, 2.50 etc. ?

and for the rear 2.15, 2.50, 3.50 etc.?

I have multiple options on rim size but I’m unsure as the most favourable for what I want from the bike.

Thanks for the response TwoMany!

 

[arcticXS]

I guess the tyre clearance with regards to chain and swing arm will then dictate suitable rear rim size. 120 or 130 tyre width is the limit with the stock chain run, I believe. And front rim should be a bit narrower than the rear rim.
Going for 18" front and rear makes sense for tyre selection, but on the other hand, 19" rear (and front, obviously) will raise gearing around 4 %, and allow use of larger rear sprockets. This will help with clearance between chain and swing arm when using longer shocks, which is another popular mod. Higher primary gearing is the best solution to this potential issue, but is pretty expensive.

 

[gggGary]

For "performance" street use I am mostly happy with WM5 (3.50") 18 front and rear. Caveats; performance tires in these sizes are limited, matched front and rear performance 18" AFAIK don't exist. Running tubes in tires on the track? hmm. A 3.50 18 on the front made mounting removing stock calipers complicated (read time consuming) changing to calipers with inner pistons, clearance gets to the spokes can be non existent.

I have another rear that is lighter and should be a good fit. As always fitting small, close to the center line XS sprockets can be an issue.

 

[Bewarethemoon]

For "performance" street use I am mostly happy with WM5 (3.50") 18 front and rear. Caveats; performance tires in these sizes are limited, matched front and rear performance 18" AFAIK don't exist. Running tubes in tires on the track? hmm. A 3.50 18 on the front made mounting removing stock calipers complicated (read time consuming) changing to calipers with inner pistons, clearance gets to the spokes can be non existent.
View attachment 138687 View attachment 138688
View attachment 138689

I have another rear that is lighter and should be a good fit. As always fitting small, close to the center line XS sprockets can be an issue.

Hi gggGary, thanks for the reply!

Tubes in tyres for mild recreational track use, what are the issues regarding this? I’m sorry for my ignorance, I’m very new to this and trying to educate myself as much as possible.

Daniel.

 

[gggGary]

Couple issues are bandied about; about all wider tires are designed tubeless. Fitting a tube increases weight and thickness, raising tire temps. Tubeless tires have a more textured interior compared to designed for tubes tires. Might increase chance of wearing a hole in a tube? Not likely n issue in mild track time use. show us pics of your parts n assembled wheels? Would like to see them!

 

[Bewarethemoon]

Couple issues are bandied about; about all wider tires are designed tubeless. Fitting a tube increases weight and thickness, raising tire temps. Tubeless tires have a more textured interior compared to designed for tubes tires. Might increase chance of wearing a hole in a tube? Not likely n issue in mild track time use. show us pics of your parts n assembled wheels? Would like to see them!

I have a collection of parts packed in boxes in various places at home at the moment

Bikes in the workshop undergoing first few steps of fabrication work, I hope to have the wheels and all parts assembled so the build is in rolling mock up stage within the next few months, as soon as I’ve reached this milestone I’m going to start a build thread

Daniel.

 

[Bewarethemoon]

Couple issues are bandied about; about all wider tires are designed tubeless. Fitting a tube increases weight and thickness, raising tire temps. Tubeless tires have a more textured interior compared to designed for tubes tires. Might increase chance of wearing a hole in a tube? Not likely n issue in mild track time use. show us pics of your parts n assembled wheels? Would like to see them!

I’m planning on ordering a set of rims and hubs from Cognito Moto, probably be Sun Rims.

I’m think both 18”, 2.15 front and either 2.15 or 2:50 rear, does that sound about right?

I’m thinking that keeping close to stock dimensions will keep it as it was intended, a little more “flickable” into and out of corners and that there’s nothing to be gained on these bikes by using wider rims & tyres.

Is this correct?

Daniel.

 

[member28833]

Before a final decision is made on rim sizes, be sure your tire choices are also avaliable in those sizes.
An 18" front could limit the tire choices.
I experienced this very issue with a dual sport BMW 18" front wheel.
-RT