HPN Gears for 5 speed Transmission

[davidswanson]

The Germany company HPN (www.hpn.de/english/english.html) makes a lower first gear and higher 5th gear for the 5 speed transmission. I am interested in using both of these you get a 5% change down on 1st and 5% higher change on 5th. I have a 1991 R100GS -PD european bike. Has any one tried this and do you have any recommendations about whether it was worth the trouble?

peace

[jbcollier]

No experience though I am thinking of the same thing myself. I run a R100R powered hack. Here is one site on ratio swapping:

http://www.gunsmoke.com/motorcycling/r100gs/tranny/index.html

I think your tranny should also need the circlip mod:

http://www.gunsmoke.com/motorcycling/r100gs/tranny_circlip/index.html

[jbcollier]

PS: How expensive are the gears? Don't worry I am sitting down!

[davidswanson]

first gear is listed as costing 117,60 EUROs 5th is actually requires two pieces and costs a little more. This company is the company that prep-ed the official factory R series GS bikes that BMW raced in the Paris Dakar races. The bikes they build are amazing if you clik on the bike picture they show examples and specs for what they build.

[davidswanson]

very helpful stories in the link. I am located in the bay area, where he lives as well, so I may used the vendors he mentions to do the work. Unfortunately he does not mention if he was pleased with the end result in terms of driving. I am going ahead with this as i have to take out my transmission to have it checked since it is hard to shift in to 1st and 2nd and I would like the idea of a lower first and higher 5th.

[jbcollier]

Please do post your evaluation as I may want to do the same thing this winter.