My 09 RK std- with the stock alum wheels continues to loose air pressure.
In just 4500 miles I have adjusted the pressure 4 times. all the valve stems are tight and not leaking, the book calls for 36 frt and 40 rear.
The frnt is leaking to 31 and the rear has leaked to 32.
Last night I checked and the frnt was down to 33, but the rear was holding 40 psi after 4 days and 300 miles.
A royal pain to get a good reading on these valve stems but it can be done after 5-6 tries.
My experience in the past is that if the pressure drops-much- the tires will wear improperly and ruin them.
Is 36 and 40 too high?

 

36 and 40 is dead on ... get yourself a little slime compressper and keep them pump up i never leave home without mine ...

 

what is a slime compressor?
Ya mean some way to pump up a low tire or do ya mean to put some sealant in the tire to stop the leaking?
I have a co2 kit- but hate to have to load up the tire with gunk.
I am leaving for sturgis wednesday.

 

Just put pure nitrogen in them.

 

The nitro would work if I was changing psi due to heating/expansion. not the case.
but thanks for the reply- it seems strange I have 2 leaking on the same bike. wondered if anyone else had the same problem.
I had a friend that almost was killed- and his wife when the perosity of the hd wheel gave out and went flat at 70mph. rear wheel.

 

I would get them checked out by the dealer, you shouldn't be loosing pressure in short time periods. I ignored one once and just pumped it up and it had a pinced tube which ended up us going down. I see you have mag wheels but that seems like too much of a loss, are you sure your not loosing pressure when you check them or pump them up. Another thread mentioned this guage and I really like it.

http://www.getagauge.com/

 

Thanks for the link- too late to get it in-now- say a prayer for me- 4000 miles coming up wednesday.

 

You might get a better guage locally, I think WaLMart even has one but not with the filler valve. I'd bet your are just loosing pressure when you try to get your guage on.

 

gmc- I hope that is the case-(loosing psi when guaging)
I am gonna ck on getting some 90 degree stems- then rebalance-.

 

I bought a set of 82° valve stems from http://www.motorcycleanchor.com/tire_valves/index.htm ; haven't installed them yet but they look to be very well made and are supposed to fit these bikes.

I assume you've done things like spit on the valve core (cap off) to see if the core is leaking anyway. Just because it's tight doesn't mean it's not leaking.

Other than that, it's always possible that you have a puncture that you just can't see, like a black nail or piece of wire that's ground down even with the tread. Spraying Windex or something similar on the tire tread while looking at it with a strong light will sometimes show up a slow leak; sounds like yours is very slow.

What others have said is true on these 2009s; it's hard to check pressure without losing a significant amount of air.