bought bike a fews weeks ago w/ 86k miles. on the ride home a few times i had trouble going from 1st to 2nd, kept going into neutral. not sure what grade oil was in gearbox but i changed it out immediately w/ 75w90 synthetic blend. shifting was much better for a while. it was actually siky smooth but 1st to 2nd required precise shifting. then i started to have false neutrals going from 4th to 5th so i thought it didn't like synthetic blend so i changed it to 75w90 dino. shifting was no longer silky smooth but klunky & positive like most bmw's because of the dry clutch. but i kept getting false neutrals from 4th to 5th. i don't think it's a spline issue as it downshifts silky smooth in all gears and in all speeds. and if i preload the foot shifter prior to shifting from 1st to 2nd and 4th to 5th it always goes in w/ no problems but i've never had to that w/ any other bike. just seems like a lot of work and thought process to shift "the ultimate driving machine". anyway, i read on one of the forums that bmw later recommended 75w140 synthetic for the gearboxes. so i tried that and noticed no difference. it's easy to change out but i'm getting tired of doing this. i thought i'd try one more time...... a straight 80w or 80w90 in synthetic as the 75w90 in synthetic blend seemed to work best. in the end, if i have to live w/ preloading the foot shifter prior to shifting from 1st to 2nd and 4th to 5th it's not the end of the world. but ideally, i just want to shift naturally without having to think too much about it. is this normal for the k's???? any suggestions or thought? thanks.

Bill

Hey Bill,

You might try the Redline synthetic as it's suppose to not be "too slick" for manual transmission synchros. I have not tried it in a brick yet, but it was outstanding in the cars we've put it in. Please report back with your results too.

http://www.redlineoil.com/product.aspx?pid=47&pcid=7

OG

Oldgoat wrote:Hey Bill,

You might try the Redline synthetic as it's suppose to not be "too slick" for manual transmission synchros. I have not tried it in a brick yet, but it was outstanding in the cars we've put it in. Please report back with your results too.

http://www.redlineoil.com/product.aspx?pid=47&pcid=7

OG

hmmm...... i used redline in my '92 saab 900 turbo and the transmission blew up in less than 10k niles after the change over. also read on one of the bmw forums that a shop was seeing lots of transmission failures w/ redline. thanks but i'll pass on redline. i went w/ castrol 75w90 full synthetic and so far a so good after a quick mile ride. will update later.

Can you post a link to that board thread Bill?

Thanks,
OG

Oldgoat wrote:Can you post a link to that board thread Bill?

Thanks,
OG

man, i looked at LOTS of stuff when doing the research and didn't bother to save it. you can do a search for k100 gearbox or transmmsion & redline and i'm sure you'll find it. as a matter of fact the author joked about how he wanted k bike owners to keep using redline so he could keep charging them for replacing transmssions. regarding my sabb 900 turbo, i told the owner of the independent saab dealer where i purchased it that i was going to replace the tranny fluid w/ redline. this older gemtleman had been selling saabs exclusively for decades and his immediate comment was "i wouldn't do that" figuring he was an older guy not in tune w/ the latest technology, i blew him off. big freakin' mistake!!!

Hi there, regarding your difficulties when shifting from 4t to 5t, I remember having the same troubles when just getting the bike, 5 years and 28000 km ago.
Reading in various forums I learned that this gearboxes are not as precise as their Japan counterparts and you need to get used to them, and in fact afther a few km and a little practice all the shifting problems dissapeared. Also found that adjusting the shift arm to your shoes is helpfull and, very important, that a good lubrication of the gearbox's input spline, smoothes both clucth and shifting action.
Hope this helps.
Best regards

JAP

japuentes wrote:Hi there, regarding your difficulties when shifting from 4t to 5t, I remember having the same troubles when just getting the bike, 5 years and 28000 km ago.
Reading in various forums I learned that this gearboxes are not as precise as their Japan counterparts and you need to get used to them, and in fact afther a few km and a little practice all the shifting problems dissapeared. Also found that adjusting the shift arm to your shoes is helpfull and, very important, that a good lubrication of the gearbox's input spline, smoothes both clucth and shifting action.
Hope this helps.
Best regards

JAP

i was afraid you'd mention the infamous spline lube. we have a short riding season here in the new hampshire and i just can't sacrafice 5 hrs for a simple lube job. what a dumbass design!!! however, i do plan on doing the splines next winter. i have a heated facility & will be able to take my time and do it in piece meal. i tried adjusting the gear shifter up a notch as i have big feet but it got worse. i had to really struggle to arch my foot up to shift up and when i had to shift down i found the lever was a bit too high. so it's back down where it was. ideally the shifter needs to be offset a few inches to the left so that it lines up more appropriately w/ the foot peg so i don't have to twitch my foot inward to shift. what another dumbass design!!! but you're right about practice makes perfect. if i really concentrate on my shifts it goes in fine. but it detracts from the enjoyment of riding. i have enough to concentrate on, like the old ladies who pull out in front of you WITHOUT looking both ways!!!

I'm afraid that the BMW gearboxes need to be treated like a frisky colt - with a firm hand - in this case a firm foot. Namby-pamby gearshifts result in false neutrals. Learn to live with it. A little extra gas on downshifts help a lot.

Having said that, the current thinking on this síde of the pond is that Castrol 75W/140 is the right stuff.

japuentes wrote:Hi there, regarding your difficulties when shifting from 4t to 5t, I remember having the same troubles when just getting the bike, 5 years and 28000 km ago.
Reading in various forums I learned that this gearboxes are not as precise as their Japan counterparts and you need to get used to them, and in fact afther a few km and a little practice all the shifting problems dissapeared.
Best regards

JAP

Yep, I found plenty of neutrals until I got used to it. Be firm with your shifting.

after 4 oil changes (dino & synthetic / 75w90 & 75w140/ castrol / amalie / walmart brand) to my gearbox in 3-4 weeks the conclusion is that it definitely prefers Walmart branded (i believe it's valvoline) 75w90 synthetic blend which is what i had in it initially. but after a 120 mile trip where i had 3-5 false netrals from 4th to 5th i decided to try something different. w/ the synthetic blend and a bit more concentration, no more false neutrals!!!

For what it's worth, a good shifting technique is required. I didn't notice much of a change when I used synthetic.

Good luck!