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Confused about Tire Selection

Pabeye

Older than Dirt
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I've searched the forum a bit and can't seem to find the answer to my tire questions.....

My '78 SOCH CB750 has Conti tires Front is 3.50 / 19 and rear is 4.50/17

1) I do not find a whole lot of selection in these sizes from The MC Superstore and Bike Bandit. Most I did find are "Tubeless" I have spoked wheels so I don't think that tubeless will work. Can I run a tube in a "tubeless" tire?

2) I think Id like to go a bit wider in the rear......metric conversion to a "130/90" OK maybe even a 140?

3) I'd really like the two rims to be closer in size. ( true cafe looks in my mind is two rims same diameter, although there is a 2" difference in the CB's rim size it does not appear to the eye to be THAT different) What would my options be to bring the front rim down to a 17" or an 18"...........how would that effect the handling?

As always input appreciated!
 
You CAN run a tube in a tubeless tire. Tubeless tire on a non-tubeless rim can let the tire slip on wheel to wreck the tube stem, it tears it off. You pretty much MUST run rimlocks. BTDT. Beware, you can get wider tire but the number on the end, 90 in that case can make tire so short in height that you look like a dirt bike, bigger looking up front than back. I had that effect with a 130-18 tire rear and a 3.50-19 up front. Yes, you can shrink front wheel and doing so decreases trail. Ground clearance (think smashing header if you have one) will decrease.
 
Thanks AMC........I think I'm going to go with Metzler Lasertec's..........listed as tube/tubeless.... a couple of guys on the site recommended them..........:)
 
A new question.....is it OK to mix two different tire brands on F & R.........

I was thinking G515-G Front Tire and

RS310 Durotour Rear Tire

OR the Metzler Lasertech F & R

Thoughts? Thanks as always
 
So do I. Be careful to look for any tire marking indicating direction, some have them depending on the tread pattern and if run backwards can be dangerous in rain. They may have an arrow showing which way to turn.

Be aware that tubeless will run on tube type wheel but sometimes need rimlocks to keep from spinning the tube to instant flat at hard braking, my spoked CB550 had to have them using tubeless tires on it. I tend to compression brake a bunch sometimes and what did it. The tire doesn't lock as well as on a tubeless rim and can spin on rim to take the tube with it, then the stem severs.
 
When I worked as a service manager at a Honda dealership, I wanted a definitive answer to the tube in a tubeless tire question. The four tire companies I contacted, Dunlop, Michelin, Bridgestone, and Metzeler, all recommended if you run a tube in a tubeless tire to go up one level on the tires speed rating due to issues with higher heat caused by the tubes contact with the tire at high speeds.
 
We also had customers who had converted spoked wheels to tubeless as is popular in the mountain biking world. They would use a heavy duty rim strip tape made just for the conversion, and then run 4 to 6 ounces of tire sealant to stop any air leaks. I have done this on a mountain bike wheel, and it works very well. But, motorcycle tires are subjected to more lateral force, and much higher heat than a bicycle tire, so I just don't think I personally would trust it. 100 mph+ with a little tire sealant holding the air in the tire would make me a little nervous to say the least.
 
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I ended up with the Metzler Lasertechs, running on spoked wheels with tubes. I installed them back in September, and have had no problems so far.....NOTE I have not ridden more than 50 miles and no more than 80 MPH, but so far so good!..BTW.......I have no plans top go much faster. I gave up the 150+ MPH runs a long time ago.....:bike:
 
I drove tubed tires on tubeless Comstars for years at up to 130 mph and zero issues. Tubeless using tube and rimlocks like said on spoked wheels. The only issue I ever ran into was with heavy braking, the rimlocks fixed that.

If you can stand the look then simple sheetmetal screws drilled into side of rim to just bite the rubber of tire and you won't have issues at 200 mph, how the race cars do it, zero issues with 1500 hp. BTDT.

Unless running a race slick roadracing the tires do not get hot, you wanna see hot then check out how hot the spacesaver car spares that are very small OD get when using them. In the summer here in Texas, they almost melt-you get a serious burn on hand if you grab one being silly. I do not see how on earth they don't pop.
 
I was just passing along some suggested info from the tire manufacturer as I assume they probably know a little more about it than I do.
Race cars definitely do not screw sheet metal screws into the tire casing, they use a dedicated wheel set-up with beadlock rings. This set-up pinches the bead of the tire between the rim and the lock ring. The bolts holding the lock ring on do not go through the actual tire casing itself. Plus the bolt holes all have to be sealed to keep air from escaping.
You should never haphazardly give dangerous advice such as running sheet metal screws into a rim and tire to someone on a forum, as a lot of people here will take you at your word and go do just what you suggested. It would also be rather silly to introduce screws into a tire sidewall when you have a tube in the tire. Please think about what you are doing and don't get someone killed from a high speed blow out. Advice on something you are an expert on is great, and is always an asset to the forum, but advice on something you don't understand is dangerous and bordering on criminal.
 
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