Type of tire for '72 CB350

[sbelshe]

I've been looking at tires for a '72 CB350. I read lots of things about tire conversion and am looking at slightly bigger and more aggressive tires. I am considering something like:

Front: Pirelli Sport Demon 100/90V-18
http://www.motorcycle-superstore.com/6243/i/pirelli-sport-demon-sport-touring-front-tire

Rear: Pirelli Sport Demon 110/90H-18
http://www.motorcycle-superstore.com/6244/i/pirelli-sport-demon-sport-touring-rear-tire

I admittedly know very little about this. I've done a lot of research to learn as much as I can. But I don't know what ratings I should be looking at (H, V, R, etc), should I stay away from a more sport bike tire like this? And most importantly, I've read posts about tubed tires and non-tubed tires. I currently have tubes, do all of these tires require them?

Sorry for the ignorance, hard to parse all of this out so I'm looking for input from people with experience.

Thanks

 

[mydlyfkryzis]

110/90 is a big tire for the front. Similar to a 4.50/18. Doubt if fits between the forks. You also would need at least a 2.15 inch wide rim....with a 2.50 inch wide rim being preferred.

tour bike, on a good day, with the RIGHT size tires will barely do 100 MPH. H rated is sustained 130 MPH....S Rated would be the most suitable. You won't be doing 118mph for hours on end....

Front should not go over 90/90-18

Your stock rims are 1.60 in the front, 1.85" in the back....

Over sized tires on a CB350 is alright for museum pieces that are never ridden....

But I am sure there will a few people that say go for it.....Your skin (literally), your money.

Some charts on Tire size versus rim width, rim size measurements. The grey area in the Tires size chart are the recommended sizes, STD being the "normal" selection.

(Also, Wider rims on the standard tire sizes will actually improve handling)

 

[sbelshe]

Thanks for all the great info. To summarize, you reccomend S rated tires, 90 on the front, 100 on the back for maximum safety and ideal performance. Do these tires need different tubes than the older tires?

 

[mydlyfkryzis]

ER, no....The old tires and new tires need the same tubes they sell today....You can use a tubeless tire with a tube, but on spoked Honda Wheels, you can't be without a tube.

You really are best with the original size, 3.00x18 front, and 3.50x18 back....

There are nice tires for this application in those sizes.

3.00 is an 80mm width, 3.50 is a 90 width. The correct tires for these still use the older sizing numbers.

If you are looking for good handling, the OEM size does best. the Chassis and forks are not stiff enough to use a larger , more modern tire. The will roll, but handling will be slower and not as nimble as stock.

Heidenau, Duro, and a few others make modern versions of the old tires, appropriate for the speed and weight of the old CB's.

Many will tell you wider works, and the bike is ridable with over-width tires. But a bigger, heavier tire reduces responsiveness, acceleration (more rotational mass), increases the weight of the bike, and makes it handle less well. I can't say the bike will be unridable, but if you rode a stock bike in good condition, then got on a bike with fatter tires and no fork brace, you would wonder why would you not stay stock with the better , lighter feel.

Like cars, some like the handling of a Miata, others prefer Large Buicks...ME? I prefer better handling and performance. Rather drive a Miata then a Big ole Buick.

 

[sbelshe]

Haha, I hear you. I'm probably somewhere in the middle. I ride my bike pretty passively. Small streets, rarely over 50 MPH, so performance is not crucial as long as it's safe. I'm trying to balance the aesthetics of the cool wider tire on a raw cafe, and making sure I'm not doing something unsafe or something that will drastically change the handling. Small differences are no problem.

I have 3.00x18 and 3.5x18 Duro's that came on the bike now, and they just don't seem to match the style of the rest of the bike. Thin, radial style tread, almost looks like a dirt bike from behind with that thin tire and my cafe seat. Though I don't ride aggressive, the bikes style is more that direction.

 

[mydlyfkryzis]

Haha, I hear you. I'm probably somewhere in the middle. I ride my bike pretty passively. Small streets, rarely over 50 MPH, so performance is not crucial as long as it's safe. I'm trying to balance the aesthetics of the cool wider tire on a raw cafe, and making sure I'm not doing something unsafe or something that will drastically change the handling. Small differences are no problem.

Slow handling is less safe than quick handling. I hope you never test it. Someone pulling out of a parking space or lot, and you need to make a quick maneuver, then it becomes important. Slow handling at 75 MPH is probably nicer. Slow handling, at 30mph, is a nuisance.

Good luck on the wider tires....You at least have the opportunity to see the difference directly.

I used to use wider tires, as I was more car oriented, and thought they would be better. That was in 1980's. Older and Wiser, I use the stock sizes now, with wider rims.

 

[sbelshe]

Older and wiser = good advice. Appreciate all of the insight and advice.

 

[wahvtec]

im running 110 90 18 rear, and 100 90 18 front. The shinkos have somewhat of a wide shoulder, and i had to modify the front fender a little. The rear still has room. Handles well for me but im kind of a slow cruiser kind of rider. I can get pictures if you would like.

 

[sbelshe]

That's great to know, pictures aren't a necessity as I don't want to put you put but are of course welcome. I enjoy seeing different tires on different setups as the tread and look of the tire become a part of the look of the bike.

Thanks

 

[wahvtec]

Here is a few, hard to really show all the fitment details, but the front wheel is tight with a fender. There is a decent amount of room in the rear near the chain, and people comfortably fit 120's, and i find that believable. Im pretty happy with my tire sizes, but next time may go with one size down in the front if i choose another wide shouldered tire.

 

[mydlyfkryzis]

You are probably going to rub on the front. Wheels and tires are not rigid. They do move a small amount. Spokes and rims flex, the tire flexes....

Many people do not seem to believe that Honda actually designed the bikes. They can be improved, but clearances and such were designed with a safety margin.

Clearance like that makes me nervous....

It is a bit ironic to put larger tires on for what you believe is better handling, but a fatter tire does not handle better in this application, and there is a little safety loss, and possible danger...

It is likely the tire won't rub bopping about town, but the first time you need 100% steering or braking and the tire rubs and upsets handling, well I'd rather not think about it. I slid along pavement once, and intend to avoid doing it again.

They look nice, for sure, but a smaller "look nice" tire would be better, IMHO

 

[sbelshe]

wahvtec, thanks for the pics. Bike looks great and I love the look of the wider shoulder. And mydlyfkryzis, thanks for all the input. Good balance of opinions and elements to weigh.

 

[wahvtec]

Yeah man total joke build, all of my infinite resources allow me to build joke bikes while my completely restored BSA museum piece takes up dust in my motorcycle warehouse....


No its not a joke. Its the most bike I could throw together starting from a $350 barn find on a graduate student budget. Its ugly it braps around town, and cranks when i hit the button and twist the throttle. I love it is my bike and i don't give a d*** what you think. Just trying to help someone with a tire size questions. thanks for your addition to the topic. Happy riding

 

[sbelshe]

xb33bsa, why would you just jump in for no other reason than to talk shit?