H: Hubs, Wheels and Tyres Buying Tyres for a Rapide

[oexing]

I don´t remember, maybe too long for road use. At that time I did not expect inner tubes ever to be a problem to buy from reputable companies. I would have got me a number of them but as so often you only learn much later how times are achanging . . . . .

Vic

 

[Bill Thomas]

If I had my time again, I would have bought a shop full of Red Arrows, 19" ribbed front and 18" rear,
Best tyres I ever had, Rode like a dream !, Don't care if they had got hard.

 

[Jonathan Lambley]

Jon, I am lead to believe that Motocross tubes are not recommended for road use, definitely a case of thicker not being better, something to do with generating heat.

Peter,
I did a bit more digging. I have contacted an Andy James, Operational Marketing Manager (Motorcycle & Scooter Products) at Michelin Tyre PLC. He initially said there was no real benefit to using thicker inner-tubes in order to prevent punctures but then I pointed out that I've fitted them to prevent punctures around the valve. He did say UHD tubes are not suitable for modern bikes ridden at sustained high speed useage but okey for older machines. This was his final reply, which i think is interesting.
Maybe the jury might still be out but I'm going to see how this UHD tube performs.
Cheers Jon
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Morning Jon,
Thanks for providing the additional information. A Michelin UHD tube on older lower performance machines won’t cause any problems at all in use. We should be looking at why inner tubes are failing though and remedy the cause not the symptoms. Splitting and tearing around the valve is usually down to corrosion or roughness in and around the valve hole in the wheel rim. Often this leads to an enlarging of the hole which allows excessive movement of the valve and subsequent wear. This can be remedied by sleeving the rim hole, and a flexible plastic washer could be used between the tube and rim. This enlargement and roughening of the area can often be in part due to incorrect fitment of the inner tube locknuts. It is very common to see one of the 2 locknuts fitted inside the wheel rim, bolting down the conical washer which is shaped to sit nicely directly against the rim and inner tube. The 1st lock nut should be run down to lightly touch the wheel rim, and then be backed off by half a turn and then the 2nd lock nut run down and the two tightened together before adding the valve cap. Locking the tube to the rim is not recommended, some leeway in this area is welcome so the tube and valve can flex naturally without restraint, hence backing off the lock nuts from being tight against the rim. Splits in the valve area can also be down to ageing of the inner tube - how old is it? Inner tubes should be changed at every tyre change, and on lower mileage vehicles we recommend for safety that tyres and inner tubes are changed at 10 years old regardless of tread wear. The valve hole can also allow contaminants in which can cause the valve to corrode. Having the lock-nuts very close to the wheel rim can help to avoid this, as can using a small amount of silicon sealer or grease on assembly.
Best regards, Andy JAMES
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[Peter Holmes]

Well thats very interesting Jon, my only comment would be isn't a 125mph Black Shadow a high performance motorcycle? especially when that speed is sustained for long periods, he said with tongue very much in cheek!

 

[Jonathan Lambley]

Ha, I knew you'd say that Peter. A valid point but I think he meant more like R1, Z1300, XJR1300 etc.
I told him what bike it was for, albeit a Rapide but I think you're covered. Its always good to get professional advice on such things. Anyway wish me luck !!!!

 

[davidd]

I believe that some land speed organizations had to deal with accidents that may have pointed to the use of inner tubes that were used at high speeds causing excessive heat or chafing. I think that I remember that the DRLA changed its rules to require all vintage bikes to run mags with tubeless tires. This was back a few years. I remember that Stuart Hooper had to change his wheels one year to comply. At the time, I was gathering parts for a Comet land speed racer and I decided to buy mag wheels for it. There was no rule requiring the use of spoked wheels on vintage class bikes, but there seemed to be no problem from a rider's point of view in using mags. It was more an issue of style, which is easily trumped by safety. Because such a change is relatively easy, the specific reason for doing it may have been overlooked. The speeds involved were probably higher than most folks could reach on a vintage bike. I would note that Alp is running mags on his Vincent.

David

 

[vibrac]

Ah ha! so all that nut underneath the rim and nut on the valve cap is what I always thought... NBG
I do like the idea of backing off I also like the idea of a trace of silicone sealant underneath another reason why I did not like the nut on cap idea. at last I know where to put my nuts!

 

[MarBl]

For the Roadrider, there are no rear tires listed with a minimum rim width of 1.85"

The 3.25 x 19 Roadrider MkII has a minimum rim width of 1,85" and can be used front and rear.
https://www.avontyres.com/de-de/reifen/roadrider-mkii?searchtype=tire&cartype=motorcycle#

Strange enough, with a width of 3.9" its even wider than the SM A 3.50 x 19 with its 3.7".

I have it on the rear of my Venom and so far it performs very well. Performance wise I'd compare it to a BT45 (which I run on the Venoms front).

I will try it on the Rapide with the 3.00 x 20 AM6 on the front.

 

[TouringGodet]

I mentioned the 3.25 x 19 Roadrider Universal tire. I am distinguishing between a true “rear” vs the Universal front/rear.

 

[MarBl]

I am distinguishing between a true “rear” vs the Universal front/rear.

That escaped me, thanks for the clarification.

Another option, I was considering, would be a combination of WM2 x 21 front rim with 90/90 x 21 tyre and a WM3 x 19 rear rim with 100/90 x 19 tyre. That would allow the use of BT45/46 tyres.
However a WM2 x 21 front rim doesnt seem to be readily available. Does anyone know a source, that stocks them or would that be special order only?