Anyone with the HPN lower 1st gear in their R100GS?
 

Hello there!

I have just had a HPN low 1st gear and a tall 5th gear installed as part of a complete rebuild of the gearbox on my 1993 R100GS. All of the work was completed at Ted Porter’s Beemershop near San Francisco.

Since reassembling the bike, I have now ridden it for approximately 30 miles. Everything seems to be running smootly except for a a new strange noise that I am unsure of: whenever I drive in 1st gear, the transmission makes a whining/whrring noise. It is very similar to the noise that a manual transmission car makes when driven in reverse. This noise only happens when moving, with the clutch out, in 1st gear.

Has anyone else installed the HPN lower 1st gear into their R100GS? How does first gear sound?

I have spoken with Ted Porter and he admits to not really knowing how the lower first gears sounds when being driven, and he suggested that I email HPN. I have done so, but I was also hoping to hear from those that have actually riden with this modification

Many thanks!! James

HI james!


We have 1.and 5 done too. But there was no diffrent sound to before...

Its better to call HPN, emails get lost..... Call them and ask for Klaus Pepperl he speaks pretty good english!


Greetings from OZ Werner+Claudia

First of all - very important!!!
Are you and your mechanic absolutetly sure he did install an X:ed 1st?
:taz:

Second - which hypoid are you running. And,... how high up are you filling your gearbox?
:Beach:


Yes - the sprockets can whine.:eek3:
Causes seems to possibly be "tight fit" and/or poor EP-hypoid.
Test Omega 690 80/90 GL7 (Magna Industrial Ltd., Hong Kong Omega Division, retailers all over the US). Links via e.g. Distributörer av Omega olja och fett såsom smörjolja och smörjfett - Smörjteknik Norden AB .


Is your gearbox getting warm or maybe even hot ?
:devil2:


Personal reflection on the low 1st. I'm running a 32/10 final drive and lack at least one full step down under the 1st... Sure, it is a great improvement on stock, but I really need crawing, not trotting, speed in first!
:censored::wheelchair:

The 5th is ok, but I sure look for that 6th gear all the time anyway...
:scooter:

THanks Werner+Claudia and Albert!


"First of all - very important!!!
Are you and your mechanic absolutetly sure he did install an X:ed 1st?"

No, not sure, but I will ask on Monday!

"Second - which hypoid are you running. And,... how high up are you filling your gearbox?"

Running new BMW synth gear oil filled to spec.

"Yes - the sprockets can whine.:eek3:
Causes seems to possibly be "tight fit" and/or poor EP-hypoid.
Test Omega 690 80/90 GL7 (Magna Industrial Ltd., Hong Kong Omega Division, retailers all over the US). Links via e.g. Distributörer av Omega olja och fett såsom smörjolja och smörjfett - Smörjteknik Norden AB ."

Another fellow on ADV has reported that he too experiences the whinning but that it is slowly getting quieter.

At this point, after another 100 miles today, it seems to be running fine and I am not concerned. I will pass on what I hear back from HPN.

So, Albert, it sounds like you are actually riding your airhead of road!!

Cheers! James

Hi James!

Which Oil you use? The manual says Castrol gpx (i think) 90 GL5.

To be honest i wouldn't use higher grade stuff. These Engines and the Gearbox are developed during the '60-'70 They are not made for all that new stuff.

Just give HPN a call maybe they can help you!


Greetings from OZ Wener+Claudia

True - GL4, splash lubrication.

I've used Omega GL7 sticky-climbing-glueish super EP since about 1996. Smoother, much more quite, no metal shreeking when pulling out from gas-stops - tested this now for about 200 000km. There is no way I'll run any other kind of oil less I fail to get hold of Omega 690 80W/90.

What happened back in 1997 may explain why I am so determined on this aspect, as well as the broken final drive this summer.
Do this very simpel test:
Take a any kind of mechanical whisk from the kitchen assessoirs (I used a hand-powered) - spinn the whisk in the hypoid and look what happens. Then compare that with whisking Omega 690. When you do that, and see with your own eyes, and feel the difference in the whisks mechanical motions - then you know why I say what I do.

Most important question though: what happens to the large bearing?
Sorry, not even Omega 690 can stop it from failing at about 100 000km -:(

What sticks in your mind is however the even older than 1981-on gearboxes, older than the /7,... - those that have brass components; those that will be damaged by from GL4 and up. GL4 and up "attacks" brass.
All /7 can use the highest GL -:)

:thumbup1: