Going tubeless

[D Mann]

What modifications need to be done to the stock wheels to go tubeless? I remember a post about drilling out for the valve stem, but now I cannot find the info.

[wilcom]

I too would be interested in the answer to this one. I was going to go tubeless the last time I retired.

 After looking at the rim I didn't see how the tubeless stem would seat. Looked as if I would have to machine a flat spot around the hole.  I had never heard anything like mentioned in the numerous threads on Tubed or Tubeless.

[montmil]

I run tubeless on my '81 R65 without issues now for the last 4-5+ years.

Your choice of tubeless valve stem -straight or angled- will drive the need to ream the valve stem hole to the size spec'd for the stem. Properly done, it's no big deal. Angled stems, not the 90 degree ones- are nice. Easy to add air.

[Tony Smith]

What modifications need to be done to the stock wheels to go tubeless? I remember a post about drilling out for the valve stem, but now I cannot find the info.

If you have "snowflake" wells, then to be legally correct the modification required is a set of wheels actually designed and approved for tubeless.

Having said that, plenty of people run tubeless tyres and seem to experience no problems at all, and to be honest I have never heard of an accident that was attributed to running a tubeless tyre on a snowflake rim.
 
Given that simply throwing your leg over a motorcycle involves the voluntary adoption of a certain amount of risk, if you wnat to do it, go right ahead.

If I were going to go tubeless I would be inclined to put a rubber bung in the existing valve hole in the rim and drill a new one in a place more easily accessed by the average service station air chuck.
 
If that does not appeal I would do what I and thousands of snowflake riders already do and carry an adapter so that you can get air in and then after removing the adapter, adjust the air pressure with the accurate gauge of your choice.

I do not recommend the use of permanent right-angle adapters as I am uncomfortable both with the amount of force potentially generated and where that force goes.

[D Mann]

OK Thanks, I thought there might be a standard size that I would be able to prepare for.

[Barry]

I don't run snowflakes tubeless but I've give it some thought and assume you would need some thing like this together with machining flats on the rim. They do seem to come in different sizes . I 'd find the slimmest stem first and machine it to that.

I'm not a fan of angled valve stems either. I did some calculations recently. If the angled portion of the valve stem weighs 10 grams (wild guess) the bending force on the stem at 100 mph is  4.3 KG or 9.5 lbs.

[montmil]

And we all know that most R65s spend their time at 100 mph.

[Luca]

Those calculations were with a 90 degree-stemmed tube though, where the valve stem is left to float in the hole in the rim and there is a chance to stress the tube rubber around the valve.

With a sturdy, screw-type independent valve socked down to the rim you don't have a tube to worry about.

8-ball caps on angled valves take your tires down one speed rating  

[montmil]

The angled tubeless valve stems on my bike are in line and parallel with the snowflake spokes.

Eight-Balls, eh Luca? On Friday nights rippin' up Rhode Island, do ya switch to Skulls so no one recognizes you?

[Barry]

And we all know that most R65s spend their time at 100 mph. Roll Eyes

Well it seemed a convenient round number to use     It sounds like lots of people are using angled valve stems so I guess they must be OK. The centrifugal calcs do highlight how important wheel balance is though.

Is it just me or did BMW machine the valve stem hole a little closer to the large radial spoke than they needed to.  I still don't have a problem fitting a car type foot pump on to a standard straight valve stem. Preferring to have the correct pressure before I set out I've never added air to a tire at a petrol station so I've no idea whether their air pump fits or not but I have a removable right angled adapter if needed. Pumping tires at home is an obligatory task when they need doing every week or 2 weeks at the outside and you don't fill the tank that often.

[DanMay]

I was planning on going tubeless on my R65LS, and asked the question a few months ago.  I believe the R65LS rims are closer to the K-bike rims than the snow flake R65 rims.  I ordered these BMW valve stems to convert (but have not actually done it yet).

   Part#           |Description                             |  Each      |  Total
-------------------|----------------------------------------|------------|
  2/36321452748    |VALVE - D=8MM (to 06/86)                |       $6.89|      $13.78
  2/07119931697    |WASHER - 8,4                            |       $0.50|       $1.00

[D Mann]

OK I have been looking around and it seems to me like I should go with the type of valve stem that has the nuts to hold it on the rim. To me the rim looks way to thick to try and get one of the snap in stems to work.

The BMW valve stems, will they fit without drilling the rim?

Thanks for the help so far guys I will get it figured out.