Help with deciphering tranny gear sizes (R1150RT)?

[KMG_365]

As soon as I have a garage back I'm doing a tear down and rebuild on our 2002 and 2003 R1150RT's. They've both got around 100,000 miles on them and I want to avoid another debacle like the one that cost us our two days in Washington D.C. en route to the last UnRally.

 

In checking the parts fiche for tranny rebuild bearings, etc. I found multiple listings for some of the gears!

 

03: 23 00 2 330 251 shift gear wheel 2nd gear

03: 23 21 7 675 168 shift gear wheel 2nd gear (EVO Z=40)

04: 23 00 2 330 180 needle cage (28X32X17)

05: 23 21 2 330 210 support (28,1X36X1,5)

06: 23 00 2 330 254 sliding gear

06: 23 21 7 651 064 sliding gear

06: 23 21 7 675 170 sliding gear, 6th gear long (EVO Z=30)

06: 23 21 7 675 171 sliding gear, 6th gear short (EVO Z=29)

07: 23 21 2 330 206 output shaft

08: 23 22 1 228 477 lock ring

09: 23 31 2 330 181 support (29X38X1,5)

10: 23 22 2 330 207 shift gear 4th gear

10: 23 21 7 675 166 shift gear 4th gear (EVO Z=30)

11: 23 22 2 330 208 shift gear wheel 3rd gear

11: 23 31 7 675 383 shift gear wheel 3rd gear (EVO)

12: 23 22 2 330 209 gear wheel 5th gear

12: 23 21 7 675 169 sliding gear, 5-speed (EVO Z=28)

13: 23 00 2 330 252 needle cage (28X32X13)

14: 23 21 2 330 211 shift gear for 1st gear

14: 23 21 7 675 167 shift gear for 1st gear (EVO Z=53)

15: 23 00 2 330 253 support (25X36X1,5)

 

The first numbers are from the diagram that show the piece/part in question, but I didn't know I could change the gearing of my tranny!

 

The one that caught my eye was the sixth gear: "short" and "long". Now both bikes are EVO bikes, but if I had any complaint about the gearing it would be that the 6th gear's "sweet spot" is about 85mph (GPS). It kills my mileage and regularly threatens my license and I'd be just as happy to cruise at around 75-80mph if it didn't feel like I was lugging the engine.

 

Any thoughts on which I might have, which I might be able to replace, or if I should even entertain such thoughts? The individual gears are about $140.00 each, so it would have to be worth it in driveability and/or mileage, but as long as I'm ordering thousands of dollars in bearings and seals, etc.--for two bikes--it becomes less of a percentage of the whole enchilada!

[skinny_tom (aka boney)]

Any thoughts on which I might have, which I might be able to replace, or if I should even entertain such thoughts?

 

No idea, but I'm sure there's a few of us out there that would like you to order an extra set or two.

 

Hmmmmm...

 

Okay, I'm taking appointments for Jamie to rebuild your transmission...

He'll do it for the MSRP retail cost of parts plus $1000 flat rate for labor. We don't know when he'll get to it or how long it will take once your bike is in his garage, but to hold your spot you need to send me a $100 non-refundable reservation fee that will not be applicable to the cost of work. There are only 50 slots, so get your reservation ASAP. In the event that Jamie is unable to perform the work as scheduled, we will go on a long vacation/ride and tell you all about it when we get back.

[Couchrocket]

Jamie,

 

This is well and truly a WAG, but don't the RT-P's have different gear ratios and a lower top gear? Perhaps that's what you're seeing. I certainly cannot imagine anything "taller" than what we have now or we'd be lugging at 110!

[big-t]

The one that caught my eye was the sixth gear: "short" and "long".

 

Just as a pure guess,my simple mind would think that refered to the gear length,as in maybe some applications,like the RT-P used a longer gear for more strength? Just guessing

[ShovelStrokeEd]

Jamie,

As far as I know there are 3 different versions of the 6 speed gear sets. One for the GS, one for the RT and one for the S. I'm pretty sure 2-5 ratios are the same for all three. The RT and the S share a 6th and the GS is different in both 6th and 1st.

 

Your owner's manuals may help in terms of ratios. Remember primary reduction is 1.889 and is quoted as part of your overall transmission ratio.

 

I think there is another whole transmission for the RT-P, something that BMW calls "deep tooth form"

 

It may be possible to swap 6th gear between the various transmissions so you wind up with a shorter ratio (more revs/mile) although I doubt that is what is meant in the fiche. It would take more knowledge than I have to know whether just the ring gear or both the ring and slider gears need changing.

[Marty Hill]

I believe that all RT's in every other country had the lower top gear. Our rpm's jumped 1k/the rest jumped .5k at the shift to 6th.

[Bill Dennes]

Take a look at these two places:

 

1. Max BMW's online fiche for '02 R1150RT. They show a part number for a "first AND sixth ger short" tranny.

 

2. BMW's ETK for the '02 R1150R. That shows a part number for a "Sixth gear short" tranny.

 

Having just had a massive spline wipeout (VIN ZE87343, 61,000 miles) (post coming about this), I elected to order the "Sixth gear short" tranny for my '02 RT. Ordered it from Chicago BMW. About $1,600 for new everything, factory built, and with a non-overdrive sixth gear!

 

Due to other plans, this will not get put back together until very late August. Stay tuned for a report.

 

Re Jamie's question, it seems to me that the ... 675 171 gear would work, but don't forget that it needs a different intermediate shaft (about $1,100) to match that sliding gear.

 

Good luck, Mister Phelps...

[Bill Dennes]

(Too late to edit the above.)

 

The ETK also shows a "sixth gear long" tranny for the R1100R which bears the same part number as the stock tranny for the R1150RT.

 

This tells me that the "sixth gear short" tranny (23 00 7 677 012) and the stock tranny will interchange on my RT, too.

[Tool Man]

Can't you just change the primary and drive sprockets....

 

Opp's sorry...wrong thread

[David_Charlton]

I do hope we'll all be treated to another one of your magnificent'Walk throughs', enabling those of us who can wrench a bit a bit, to save a fortune not attending the dreaded dealer,good luck,lots of 'photos please

[Stan Walker]

Can't you just change the primary and drive sprockets....

 

[KMG_365]

Thanks for all the great input folks! (and you too, Mike! )

 

It looks like if I were in the market for a new spline/shaft or even an entire tranny it might be a good idea to swap out the whole thing (for the shorter gearing) and not mess with it at all. I guess I'll rip into mine and see what things look like and if I can get away with a few $100 in bearings and seals (if the gears and splines are still okay), that'll be much better on the budget!

 

I've tackled tranny's before, but long ago (only on Japanese bikes), and never had the Beemers that far disassembled so I'm a little out of my element. But as they say "Necessity is the Mother of invention (or courage in my case)! And as I have more time (and gumption) than money (or sense), I'm pretty much forced to figure it out if we want to keep racking up the miles!

 

Thanks again to all for the insight and info as well as to the lurkers who emailed me privately! I plan to make good use of Ted's Spline Lube Party DVD-walkthrough pretty soon!

 

David, if I ever get my garage put back together and can talk Leslie into taking the pics, I'll try my best to post another walkthrough.

[John Moylan]

just a bit of info.....if it's like he GS boxes, the gearbox has to be heated to 100degC to split it.......got an old cooker?

 

As for the perennial 5th/6th gear shuffle.......how about a lower final drive. There's loads to choose from....and you might even find a GS owner wanting to trade his UP !! There was a write-up on this change to an R850R in the club mag here, last month....