I'm building a 16x3 laced front wheel for an 07 Street Bob.

While shopping for the hoop on ebay I'm seeing rims with "large" valve stem holes and "small"...

Some of the descriptions say the "large" hole is for a "rubber" valve stem and the "small" is for a "metal" stem.

I can only guess (having never owned a laced wheel) that the "metal" stem is threaded for "jam nuts" that secure it to the rim.

If this is true... then this is what I want.

Also... if any one would know, who would it be that would know... what length of spoke would be used for a stock 07 FXDB front hub and 16x3' 40 spoke hole, drop center (stock) rim.

Any info offered will be most appreciated.

 

any one?????????

 

This may or maynot help you, my only experience with wheel building relates to bicycle wheels, hopefully the principles will "cross over".
With cycles, a large valve hole is for a rubber valve and the small hole is for metal ones.
As for spoke length, it is determined by lacing patterns and the difference in spoke lengths can be only a matter of 2mm. The correct length is vital. The position of where the holes are drilled in the hub can have a massive effect on the length of spokes required.
I think it is unlikely that an exact spoke length answer can be given with any accuracy. Although I am happy to be proved wrong.
Good luck.

 

man i have built a ton of wheels and not sure i have ever seen a large or small schrader valve hole, i have seen center holes and off center, as well as strait or 90 tubes but not sure i know what you are talking about

 

the small hole (metal post) is called a presta valve. its secured to the rim with a nut. the large hole (rubber post) is a schrader valve and is not secured to the rim.

the presta valve is pretty common on mountain and road racing wheels for bicycles but i havent ever seen it on a motorcycle. the main advantage is its easier to deflate the tire, for offroad, and can be used with the super skinny tires, for onroad. the main disadvantage is you'll need an adapter (they are dirt cheap but i lose them alot) for most every air pump made. presta valves are also really common on tubeless bicycle setups. presta valves are also better at handling the high pressures of road racing bicycles. but i doubt you'll encounter a need for 100+psi on your motorcycle.

i doubt you'll be using 19 or 22mm tires on your motorcycle or deflating them for offroad traction. so i'd just get the large schrader hole to make your life easier. if you really want to go presta and have schrader rims there's and adapter for that too.