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2022 R1250RT Racing Blue
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That is exactly what I've learned also.. RT-P has the lower final drive gear ratio which is used in the GS/GSA.

Simple rpm comparison at 80 mph GPS would validate the difference on the RT-P vs RT civilian.
Was at the shop getting service to my RTP so I asked the tech the question. He stated that all water cooled RTs have the same transmission and gearing, regardless of RT or RTP.
 

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2022 R1250 RT
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Was at the shop getting service to my RTP so I asked the tech the question. He stated that all water cooled RTs have the same transmission and gearing, regardless of RT or RTP.

Review of the RT-P by Revzilla and the claim of different drive line gear ratio. Would imagine a BMW parts schematic would validate what is actually in the RT-P. Skip to 10 mins in the video for the commentary..

 

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Was at the shop getting service to my RTP so I asked the tech the question. He stated that all water cooled RTs have the same transmission and gearing, regardless of RT or RTP.
Another BMW Tech that is probably full of it? Sorry to say I have met very few Techs that are actually good mechanics. Now as In cars too they rely on a computer to tell them what to do.
 

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2022 R1250RT Racing Blue
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Review of the RT-P by Revzilla and the claim of different drive line gear ratio. Would imagine a BMW parts schematic would validate what is actually in the RT-P. Skip to 10 mins in the video for the commentary..

Who knows. All I can say in riding both the 22 RTP and 22 RT, they feel the same in slow speed, high speed, 0-80mph launches, slow lock turns and cracking the throttle at 75 on either takes you over 100 without effort. Even if you could change the gearing, not sure why you would want/need to spend the time and money.
 

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Was at the shop getting service to my RTP so I asked the tech the question. He stated that all water cooled RTs have the same transmission and gearing, regardless of RT or RTP.
That's what I said, but you didn't ask him about the Final Drive! That's where the gear ratio reduction happens. I can prove it for the GS/GSA, but not for the RT-P.

Several dealers have part microfiche online, so you can look up various components!

Here's the FD for the 1200 wethead GS/GSA: FD. Note that the part number is 33 74 8 394 281, but note in particular the description, which gives the gear ratio reduction for that FD: RIGHT-ANGLE GEARBOX, SILVER - I=32:11=2,91

Here's the FD for the 1200 wethead RT: FD. Note that the part number is 33 74 8 394 283, but more important, the description: RIGHT-ANGLE GEARBOX, SILVER - I=33:12=2,75.

To the best of my knowledge, the 1200RT-P also have a lower ratio FD, but I don't know if it's the same as for the GS/GSA or a different one still. Makes a lot of sense to me, that it is so, because of the easier low speed handling that are often required of the RT-P and the GS/GSA.
 

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2018 R1200RT
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560 Posts
That's what I said, but you didn't ask him about the Final Drive! That's where the gear ratio reduction happens. I can prove it for the GS/GSA, but not for the RT-P.

Several dealers have part microfiche online, so you can look up various components!

Here's the FD for the 1200 wethead GS/GSA: FD. Note that the part number is 33 74 8 394 281, but note in particular the description, which gives the gear ratio reduction for that FD: RIGHT-ANGLE GEARBOX, SILVER - I=32:11=2,91

Here's the FD for the 1200 wethead RT: FD. Note that the part number is 33 74 8 394 283, but more important, the description: RIGHT-ANGLE GEARBOX, SILVER - I=33:12=2,75.

To the best of my knowledge, the 1200RT-P also have a lower ratio FD, but I don't know if it's the same as for the GS/GSA or a different one still. Makes a lot of sense to me, that it is so, because of the easier low speed handling that are often required of the RT-P and the GS/GSA.
Yep, I was trying to recall the fact, which I once knew about the R1100x/R1150x bikes, but couldn't put it all together, so I stayed silent. I ~~ believe ~~ on the R1100x/R1150x bikes, they actually had the GS final drive. There was also a hack many of us did, which was replacing the throttle intake tubes on the RT with the GS version, which gave our bikes a bit more pep (again, can't recall, either more top end or a stronger bottom end, but just more power because of better breathing). I don't think anyone is much interested in adding power to the R1200/R1250 bikes, because they are already pretty peppy.
 

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2019 R1250RT
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205 Posts
Pulled my leaky fork off. You can see the buildup of oil and dirt:
Tire Automotive tire Bicycle fork Bicycle frame Vehicle


It was never a large enough leak to drip down the fork tube, but there would consistently be some oil pooling on top of the dust cap after every ride. Only 22,000km on a 2019, it was leaking the entire 2022 riding season.

I noticed the top sealing boot for the joint link (also referred to as ball joint in the service manual) is a bit worn. You can see some of the rubber which was worn off. I believe this is just from the flange nut which holds the fork tube to the handlebar bridge:
White Automotive tire Light Motor vehicle Automotive design


I was going to replace the top sealing boot, but BMW doesn't sell it! You have to buy the entire joint link. About 100 USD, too much when I only really need the top sealing boot. Here is the part they sell:
Font Parallel Bicycle part Engineering Auto part


And here is the disassembled diagram of that part. Part number 1 is the worn part shown in my picture above. Kind of silly BMW can't sell this part:
Handwriting Font Parallel Pattern Rectangle
 

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2019 R1250RT
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205 Posts
Got the fork seal replaced and reinstalled on the bike. There was only about 420mL of oil in the fork. I believe it was underfilled from the factory. Even though it's been seeping for awhile, it's only a drop or two of oil per ride. The service manual states 545mL, and the oil should measure 90mm from the top of the fork tube. The amount of oil I used to get the 90mm measurement was very close to the stated 545mL.

I refilled with Motorex Racing Fork Oil 10W. It was the recommended fluid from my dealership. Here's the old oil:
Liquid Drinkware Water Fluid Barware
 

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2019 R1250RT
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205 Posts
Installed the front wheel on my bike this afternoon. I started cleaning up and found this on my bench:
Body jewelry Wood Jewellery Electric blue Circle


This is the little ring that goes on top of the dust cap. No way to install it without dropping the fork again. Pretty upset about this. I was rushing to get it done last night as I had somewhere to be. What a piss off :mad:
 

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2018 R1200RT
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560 Posts
Installed the front wheel on my bike this afternoon. I started cleaning up and found this on my bench:

View attachment 181459

This is the little ring that goes on top of the dust cap. No way to install it without dropping the fork again. Pretty upset about this. I was rushing to get it done last night as I had somewhere to be. What a piss off :mad:
Could be worse. You could have found it in the back corner of the floor of the work bench, where it bounced and rolled to, say .... about five years from now. That's par for the course with me. If there AREN'T extra parts left over when I'm done, I get kinda nervous. 🤣

So, count your blessings, and enjoy the "extra" wrenching time. 😏
 

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2019 R1250RT
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205 Posts
Could be worse. You could have found it in the back corner of the floor of the work bench, where it bounced and rolled to, say .... about five years from now. That's par for the course with me. If there AREN'T extra parts left over when I'm done, I get kinda nervous. 🤣

So, count your blessings, and enjoy the "extra" wrenching time. 😏
You're right, it could definitely be worse. Atleast I didn't have to disassemble the fork. I ripped it apart and got it all back together in about 1 hour.
Bicycle frame Bicycle part Bicycle fork Wood Metal


Something I mentioned on the other forum, and I may as well mention here; After installing the wheel and axle, I compressed the suspension several times. I then put it up on the center stand to torque the axle and pinch bolts, as per the service manual. With this method, there is obviously a little bit of weight on the front wheel, and it is in contact with the ground while torquing the axle and pinch bolts.

This differs from the owners manual. It also says to compress the front suspension several times, but then to install the front wheel stand to lift the wheel before torquing the axle and pinch bolts.

Anyone have any logic for why one way would be better than the other? Or it doesn't matter? I've found lots of conflicting information from BMW in their manuals.
 

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'21 R1250RT
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725 Posts
I've found lots of conflicting information from BMW in their manuals.
Yeah, I wonder if different engineers at different times introduced their favourite way of doing things. When it comes to these "options" I try to work out what the intent is and what can effect the outcome. Given enough practical knowledge and engineering understanding, it is not that hard to work things out for yourself.

The intent here is to make sure the forks are not twisted, the axle is pulled in all the way and it did not bend one of the forks in the process. The bouncing with loose pinch bolts supposed to do the straightening as long as the axle is only just past hand tight. I do not think that using a front stand will make a difference in any way. The load on the front wheel is not that much with the bike on the centre stand, can't see it effecting anything. I changed tyres twice now, always bounced the front and never used a front stand. The front is perfect after 42k kilometres. Go figure ;) Besides that I never seen any bike mechanic use the front stand that way either.
 
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