Tyre & Rim Confusion?!?
 

I've started a new thread because my confusion has moved to another level!

I have a '97 XTZ660 and I'm looking to get new TKC80's for it. I would like tubeless tyres but I don't know what the deal is with tubeless rims and how you tell.

I'm currently running Bridgestone Trailwings and the front tyre says it's "Tube Type" but the rear doesn't say either way and I can't find anything on the rim which gives me a clue.

The markings on the rims are as follows, but it's all Greek to me!

Front: D.I.D. Japan (I understand that bit) 96 --08 09-- J 21x1.85 1195 DOT
Rear: MORAD SPAIN 3.00 X 17 36T 1/01 E DOT

I can't find anywhere on the web that gives me any clue as to what the hell all that means. Folks have been very helpful so far with tyre size info, so can anyone help with this? A good website with the info would be good, or better still, does anybody know if I can run Tubeless tyres on these rims?

I have been watching Chris Scott's "DIY Tubeless Rims" thread with interest but it's getting a bit out of my depth.

Any advice, opinions or other info would be gratefully appreciated.

Any tyre fits just about any rim or the right size, the markings regarding tubes only tell you what it can be used for. So:

130/80 - 17 Tubeless

It's 130 mm wide (so will it clear the swing arm and fit the wheel?)
It's depth from rim to tread is 80% of the with. (So will it hit the mudguard)
It's for a 17" rim
It can be used without a tube if the wheel is set up for it.

A 120/90 -17 (nothing else) is 10mm narrower, a little "deeper" and won't seal to the bead so needs a tube regardless.

There are also older imperial sizes eg. 4.00 R 17 is 4 inches wide on a 17 inch rim with a fixed ratio on the depth.

The other numbers are date codes, load and speed ratings.

I know your XT has spoked wheels. The front is a 21" 1.85" wide, the rear 17" 3.00" wide. These seem narrow and will have a tube. There are metric equivalents, but I think you need to get them from Yamaha, not by cross refering the numbers you have.

On the tubeless thing, take a tourer and the rim could be the same size, but will be cast wheels (or special type) hence there is no way for the air to get out, hence with a tight bead (where the tyre grips the rim) it will be air tight.

You could take the tyre off the tourer and fit it to the XT (same size), but here's the crux of it, it will leak unless there is a tube and even though the tyre will still grip the rim. This means there are three practical combinations and puncture fixes:

Spoked wheel, Tube, Tube type tyre: use levers, get the tube out, fix.

Cast wheel, tubeless tyre: Fix with an external bung, remove with a bead breaker later and fix with an internal bung.

Spoked wheel, Tube and Tubeless tyre: Remove with a bead breaker and fix the tube.

(Cast wheel, tube, tube type tyre: Only ever used when the casting is porous, acts just like a spoked wheel.)

The bike manufacturers often go for option three because they think you'll never want to get your hands dirty and will ride 2000 dry miles a year to and from your local coffee shop. They fit tubeless tyres with a tube simply because they are available.

The options that were discussed in the other thread involve hardware that will sort the spoked rim so it'll run a true tubeless set up and allow an easier bung fix for a puncture. These solutions are currently rather experimental, Heath Robinson or expensive, hence the discussion.

Hope that helps

Andy

hi there if your rim is a conventional spoked rim ie spokes going through it and you can see them under the rim tape you will have to use a tube. you can use a tubeless tyre on a tube type rim but with a tube fitted , with old road bikes it is hard to find tube type tyres now so you just fit tubeless with a tube, to stop air seeping out through spokes , they are just a little more difficult to fit . some spoked rims the spokes dont go through the rims so are prosumably are made for tubeless tyres and should be marked tubeless type .but please note do not fit tube type to a tubeless rim it will not make a seal on the rim . so unless some one has come up with a way of sealing spoke ends you need a tube . take care zigzag :thumbup1:

They have on mountain bikes, I think it's a form of liquid latex which then sets. It's called Stans Notubes or something like that. Presumably it can cross over to motorbikes.

Personaly, I'd say why bother? :confused1:

Run a tube type tyre - because it's (relatively) easy to get on and off to mend a puncture. :thumbup1:

Run heavy duty tubes - because they puncture less. :thumbup1:

Carry a bicycle pump, tyre levers that YOU can get the tyre off with, and a puncture repair kit. :thumbup1:

No faffing, no messing, no air leaks! ?c?

hi my reply may have been confuseing if the rim is tube type and you carnt get tube type tyres you can fit tubeless tyres but with a tube fitted as it will not seal on the rim as well as leaking past the spokes . so as angustoyou says stick with tube type tyres on a tube type rim if you can as thay are much easyer to fit and remove. as for your xt660 having tubeless rims if thay were i would expect it to be stamped on the rim somewhere and also for the spokes not to go through the rim in a conventional way . take care zigzag

OK, so far, I think HD tubes and tubed tyres are the way forward for me. But is it worth upgrading to tubeless rims and tyres? Although they're harder to fit etc, I've heard that they puncture even less than HD tubes, and you don't have to take the tyre off the rim to fix with a plug. I also heard that tubless tyres don't blow out as violently as tubed tyres can. Will this be an expensive change, and is it worth the effort?

Thanks again, team.

You can only fit tubeless tyres tubelessly, if the rims are sealed (as posted above).

Currently the only tubeless spoked rims I've seen are the ones fitted to the BMW GS Adventure, and while they might be available to lace to your own hubs, the price is likely to be astronomical.

Also, the rear rim on the BMW GSA is very wide, and may not fit other bikes' swingarms?

If you can find a set of cast wheels that will fit (or can be made to fit) your bike that is an option too perhaps, but they are unlikely to be as strong as spoked wheels for off-road/tarmac use...

If you have a 21/18 inch wheels combo, I recommend Michelin Ultra Heavy Duty (UHD) tubes - you'd have to be going some to puncture those.

xxx

Tubed with (U)HD tubes it is then. I'm not so sure about cast wheels, they're a bit too road biased. I've heard about UHD tubes before, but haven't been able to find them anywhere. I'll keep my eye out for them.

Thanks

Both Michelin and Bridgestone do a UHD type of tube, but they are only available for 21" and 18" rims.

If you have a 17" rear wheel like I do on my Tenere, then Fly (and possibly some other manufacturers) make a Heavy Duty tube in 17", just not an 'ultra', which I guess will have to do...

xxx