Wider rear tire possible?

[HERRBAYEMVAY]

I am going to have to purchase a new rear tire soon for my '84 R65 that has the stock snowflake wheels. It has a 110/90 tire on it right now, and I would like to put a wider tire on it if the wheel will accomodate one. Anyone out there know if I can put a wider one on the rear, and if so, what the max is? Thanks!

[KBasa]

Do you have clearance at the swingarm?

Most of the manufacturers provide rim information for their tires. They usually indicate what size rim should use what size tire.

For example (http://www.dunlopmotorcycle.com/tirecatalog_tire.asp?id=10)

[HERRBAYEMVAY]

Well, I just checked on the tire for any such info, but didn't see any. I think the brand of tire currently on there (King) must be some sort of "econo" tire that the previous owner put on the bike, and I've never heard of it before. I also checked for clearance at the swingarm, and there does not appear to be much (between 1/4 and 1/2 inch_ between the tire and the swingarm itself. It would seem that based on this observation, I guess I cannot put a wider tire on the bike than what is on there now. Bummer.... Oh well....

[jgr451]

I had the opposite prob with my 84 R100 RT I suspect the wheels are the same.The tire I changed from,was slightly wider than the stock spec,there was almost no clearance at the swingarm,but enough so it did not seem to be a prob.The new,stock size tire is noticeably narrower;but I doubt it makes any real difference.:dunno

[pmdave]

The limiting factor on most airheads is the space between the left side swingarm and the brake shoes on the drive. There isn't much wiggle room, and if you try to arm wrestle an inflated tire past the shoes, you may dislodge the shoes and have to put them back in place before trying to reinsert the wheel/tire.

Check your owners manual for the correct original tire size. It's probably 400H18. You may be able to shoehorn in a 110/80V18 or 110/90H18.

An additional problem is that most of today's tires are tubeless, meaning the interior of the tire is not kind to a tube. Some tires are tubeless, but the interior is tube compatible, so it's worth asking. If you have spoked wheels on your airhead, you'll need to run tubes in the tires.

Although it might seem that a wider tire would be an advantage, a wider tire than stock may cause handling problems in corners. Best advice is to install German tires of the size and construction recommended in your owners manual.

Other hot tips: before you buy a tire, check the DOT manufactured date stamped into the sidewall. It's a code, so ask how to read it. Don't install any rubber older than say, 3 yrs. And, whenever you buy a tire, ask for a "registration card" which the dealer is required by law to provide. If he says "huh?" ask him to get one for you. Then, register your new tire with the tire company.

[pmdave]

One more trick for getting a fat tire past the brake shoes on an airhead with double sided swingarm. Place a thick piece of slick plastic over the brake shoes and rear drive. A polyethelene bag or a couple of plastic shopping bags will do the trick. The slick plastic allows the rubber tire to slide on by without hanging up.

And, lest we forget, always secure the centerstand to the front wheel before removing the rear wheel. A tiedown strap hooked around the centerstand and looped through the front wheel will help prevent the bike from toppling forward off the centerstand while you're pushing and tugging back there. When the bike pushes forward and retracts the stand with the rear wheel removed, it's embarrassing, expensive, and potentially bloody and painful. Trust me on this one.

pmdave

[Brownie]

I run an 120/90 on "Igor" (82 RS) but as a former R-65 guy, I have the feeling the swingarm geometry COULD be different; your best responses will be from the R-65 community.

FWIW: the 120/90 can be used without the 10mm spacer if desired.....have done it both ways, but I feel more comfortable with the smaller 8mm spacer for more spline "bite."

Also....."close" here means VERY close....1-2mm is fine!!