Light weight; modern rubber: 17" or 18" wheels on a CB350?

[Tremelune]

I just picked up a 1970 CL350. My plan was to leave it alone, but it needs new wheels and tires, so I'm back on my bullshit.

The role of this bike is mainly commuter. It will spend the vast majority of its life under 50mph, squeezing through tight city traffic and squirreling through tight mountain roads. Lightness matters, particularly in the wheels.

To that end, my plan was to get some aluminum rims laced with stainless spokes. I'm trying to figure out if I should stick with the stock 18" rims (the 19" front is right out) or move to 17" rims, my thought being that 17s would be lighter, have less rotational mass due to the smaller diameter, and have greater tire selection since most modern bikes have 17" rims. Maybe quicker turn-in? Any down sides I'm missing besides high-speed stability? Am I crazy to think 16" might be one better?

My plan was stick with stock widths (1.60 front, 1.85 rear), but I noticed that the CBR300 runs 2.75x17 and 4x17, and it has comparable power and weight to the CB350 (360lb and 30hp vs 375lb and 35hp, respectively)—even less for the CBR250 and CBR125, which I think run the same wheels/tires. Sure seems like a good size for modern radial rubber (even if I have to throw a tube in there).

Tangential: anyone figure out how to seal a spoked rim yet to avoid tubes? Glue the rubber guard strip to the wheel (as opposed to the spokes to allow for truing)?

 

[Sderbyshire]

I think the 17” option might look too small/silly?

I relaced the wheels on my 360 with new stainless spokes, painted the hubs and rims black, and fitted Dunlop K82 TT100 tyres, which look period bit have good performance.

Steve

 

[doc_rot]

If you go 17" i think the CBR 300 sizes would be ideal for finding tires.

Things to consider;
>wider tires require more lean angle to achieve the same turn all other things remaining equal.
>you will loose quite a bit or ride height, which may impede turning clearance further.
>Wider tires may require offset sprockets for the chain to clear the tire, and in extreme circumstances may require notching the frame.
>A wider tire my require a different swing arm for clearance, same with forks.
>Radial tires generate a lot more heat than bias ply, so you need a radial specific tube.

I'm not familiar with the cl350 so I cannot say for sure on any of this stuff. Measure the crap out of things before committing.

http://www.wheel-works.com/ was offering tubeless spoked sealing but i don't see it on their website anymore. call to find out.

Personally i would go with 18" wheels as the CL is more of a scrambler. Fat 17" tires would look out of place. 18"s will be more plug and play than the 17"

 

[themotoworks]

if you go 17 on the front, you're limiting the width of the tires you can get, old bikes like that tend to feel better with narrower tires, I think the narrowest you can get on a 17 might be 110 or so. 18" gives a lot more options on tires

 

[Tremelune]

The CBR300R runs 110/70-17 up front and 140/70-17 (which seems very common among the new small bikes), and Michelin has the Pilot Power RS in those sizes...which is a pretty sweet category to have access too. It's not like I'm dragging knees around, but it never hurts to have some extra stick during emergency maneuvers...

There are plenty of tires that are "fine" in 90/90-18 and 100/90-18, but I can't get excited to put on a set of Battlaxe or Roadriders designed decades ago, or even some of Michelin's "city" offerings that promise longevity, puncture resistance, and wet weather handling. None of those qualities are important to me...

Not sure if I could fit a 140 in the swingarm...Not sure running two front tires is wise.

 

[J-Rod10]

You're likely to end up with tires that are more capable than the bike.

The AHRMA guys are out dragging knees every weekend on Roadriders and the likes.

 

[Tremelune]

That's probably true—the CB350 frame is a noodle. My hope was that a cutting edge sport radial in 17" would be lighter than an old-ass bias ply in 18", even if wider, but I can't seem to find any weight specs for motorcycle tires.

My other thought was that, if I get even dumber and put a GSXR front on the bike, I'll have serious brakes that might keep me out of a left-turning car door, but it's possible I'm going too far down the road of customization when I should just putt around on this reasonably capable classic and enjoy the stroll...

Reeeally wish Honda would come out with a Modern CB350 like the Monkey and Super Cub. The Triumphs are too damn wide and heavy, and I just don't quite like the styling of the other retros. I essentially want a CB300R that looks like a CL350 and comes in near 300lb wet...but I digress...

 

[canyoncarver]

...... some of Michelin's "city" offerings that promise longevity, puncture resistance, and wet weather handling. None of those qualities are important to me...

I'm having trouble reconciling your statement of having a "commuter" bike and your quote above.

 

[Tremelune]

I live in LA, so I'm not riding below 50F, I'm not riding in rain, I'm likely to do 1000-2000mi per year, and so far, I'm not running through construction sites much. As such, sticky summer tires that wear out in 10k miles are right up my alley.

 

[datadavid]

Re: Light weight; modern rubber: 17" or 18" wheels on a CB350?

This thread is pretty much you telling yourself how much you know about tires and telling yourself what to buy

 

[Tremelune]

Research is no substitute for experience, so I'm hoping to find that rare person that has gone from 18" to 17" tires that can share their experiences.

Also, maybe someone has a link to tire weights...

 

[Rat_ranger]

I have 17s on my xs650, but I don't have enough miles to give a good review of them. Front is a 17x3.5 and rear is 17x4.25, 120/70 and 150/70 to keep tire heights close to stock. In the short runs I've been on so far it seems nice and stable up to 60, turns well, but is a little heavier feeling at low speeds. Once you get past about 20mph the feel is about the same as other old bikes I've ridden. But I'm also running big piston forks, 24.8* of rake and 30mm offset on the triples, and a slightly longer than stock swingarm with monoshock. For all the changes I made I'm happy with a little heavier feel at low speed with good stability at higher speed, but I can't say if it'll work as well when all is stock except the rims.