Loss of power

My '96 GS has developed a problem. In 3rd gear between 3000-5000rpm it has a sudden loss of power for about one second. After this "lurch" it runs fine and if I stay in 3rd it does not do it again. This doesn't occur in 1, 2, 4, or 5 gear only 3rd. To make matters worse it is intermittent but seems to be happening more frequently. The local dealer has not been able to duplicate the problem which I understand. They feel it is electrical or fueling related due to my description and I would tend to agree but why only in one gear. Any ideas would be helpful. Thanks

That sounds more like the classic "third gear skip" that a lot of pre-1997 oilheads develop. It seems intermittent because it's currently only happening when you downshift from 4th to 3rd and accelerate rapidly. That's how it starts. Try it a few times in a row to see if it happens every time.

The cheapest fix is to replace the transmission with one from 1997-2000. You can also have it repaired, but that is more money.

My '96 GS has developed a problem. In 3rd gear between 3000-5000rpm it has a sudden loss of power for about one second. After this "lurch" it runs fine and if I stay in 3rd it does not do it again. This doesn't occur in 1, 2, 4, or 5 gear only 3rd. To make matters worse it is intermittent but seems to be happening more frequently. The local dealer has not been able to duplicate the problem which I understand. They feel it is electrical or fueling related due to my description and I would tend to agree but why only in one gear. Any ideas would be helpful. Thanks

Morning czechman

It sounds like Jim has the problem identified.

If you want your dealer involved then have them pull up the old BMW service bulletin #2807 Gearbox, dated 1/15/98.

That covers the pre 1997 BMW Boxer gearbox skipping: "Brief power flow interruptions observed in various gears".

Cause: Gears are not correctly and fully engaged. The edges of the shift dogs and shift gears are rounded as well as wear on the shift forks.

Unfortunately, this will be a very expensive BMW dealer repair.

If you are capable of doing most of the trans work yourself then you can install later clean bearings, install new shift forks, and send the existing gears out to have the shift dogs back cut for more positive engagement.

Or, as Jim mentioned, install a used later style transmission but a good used trans is kind of a crap shoot.

Thanks for the advice. I'll try to get the dealer to pull the service bulletin

Thanks for the advice. I'll try to get the dealer to pull the service bulletin

Morning czechman

You might also try changing your transmission gear oil (save the removed gear oil in a CLEAN pan).

Then take the pan of drained oil out into the sun light & give it a stir, if the removed gear oil has a golden sheen, or golden streaks, or looks golden then you can be pretty sure that you have internal transmission issues.

If I look for a used tranny should I try for a M97? Local dealer may have a used out of a R1100RS. Would this be usable as long as the dealer checked out the internals.

Czechman,

I put a M97 from a R1100RT in my 99 R1100GS. As far as I know, there are no differences except the RT/RS unit will be painted black.

Yes, look for an M97.