BMW R1200RT/R1250RT Forum

I was pushing the bike above 100 mph when I sudden lost power.  I noticed the throttle had no return function, just loose, both back and forth.  I was able to start the motor, but not rev it. And the idle was extremely rough.I figured I'd broken a throttle cable, but when I exposed them, pulled them free from their seats, when I pulled on end, it pulled the other, so it appears the cables are intact.  Didn't take my manual with me, and couldn't even figure how to remove the tupperware for a closer look. No Beemer mechanics within 300 miles!  Help!  Any thoughts?

Have I understood correctly that the throttle cables have only been checked at the twist grip on the handlebars. Is the bike fitted with cruise control.

This video https://www.youtube.com/watch?v=2UHU4ZQ2C_Q shows how to remove the body panels (Tupperware) from a Camhead, from what I remember of a Hexhead, it's very much the same.

Yes, David.  Only checked at the grip, and does have cruise control, but was not set at the time of the failure.  I had just twisted the grip hard when it happened.

Sounds like the next step will be to remove the body panels and check the throttle cable splitter box and throttle bodies for correct movement.



The pulleys are only plastic, they can break or cables jump off.



The throttle body pulleys are also only plastic, they have been know to break too, viewtopic.php?t=93.msg42264#msg42264

Well, I'm back home with the bike in the back of a U Haul box truck I rented.  Lucked out and will drop it off for a Tuesday servicing.  You guys and my local dealership agreed on the cause, and saved me some inept and fruitless attempts to fix it in 100 + temperatures.  But I missed the Speed Week at the Bonneville Salt flats in Utah.  Really wanted to see Alp Racing's '48 Vincent and Bonnie (hence the name) pre-unit.  DID me so many helpful and kind people including to Sheriffs who pushed the bike off the road, gave me a ride 20 miles into town, where they'd already made reservations at a motel.  So, my faith in BMW's took a hit, but my faith in humanity moved up a couple of notches.  Hopefully, I'll be back on the bike by Tuesday.  Thanks for your help.

jackronner wrote:You guys and my local dealership agreed on the cause.

Which was?

The plastic bits you referenced.  Also said the rough idle supports this.

Yep throttle cam pulleys most likely , I would look at these http://www.beemerbits.com/catalog/produ ... cts_id=856

Found this video of an R1200GS throttle body being disassembled, https://www.youtube.com/watch?v=ysVctg-6iIU

The throttle cam pulley looks like an integral part of the throttle body, hence the replacement kit shown above.



In the video comments, two guys are looking for replacement pulleys.

Bing Carburetors offer replacement parts, https://www.bingcarburetor.com/throttlebodies.html

Update:  Still awaiting replacement pulleys (Both had broken!).  Deep irony:  BMW does not even carry the pulley as a part - you have to buy the whole throttle body ($713 each).  My dealer had already ordered the aluminum ones from Beemerbits,  but as it is my sole means of transport, today I've bought the plastic pulleys from Bing, in Kansas, to be overnighted to my dealer - $51 each vs. the $250 Beemer bits version.  I'll let you all know if they fit.  If you want to order them, they'll demand the "75-47 or 75-50" identification number (which, of course, is invisible without taking off the whole throttle body) not just the visible BMW part numbers.  I saw a photo first gen RT body for sale which showed 75-47 and the correct BMW part number, so it's likely it will fit, if you want to order some spares just in case.


Of course, having brought the bike back 600 miles in a rented box van through raging rain storms without incident, about 100 feet from safely returning it, someone in a large shuttle bus pulled into my blind spot (huge) as I slowly backed up - crash.  Perfect end to a perfect week. NOT.  I will not be going to Vegas with this luck.

Out of interest, have the Bing replacement throttle body pulleys been ordered with or without the shaft assembly.





Are the throttle bodies Type 75 or 77.

Without the shafts. Type 77-47 ordered.  Did not actually see those numbers as only visible when bodies removed.  Based it on 1) Pics of a body offered for sale, showing both sides, with those numbers and the appropriate part number ending with 5323, 5324 for each side, and 2) checking those same numbers on my 2005.  Still don't understand why the Bing guy hadn't enough experience to know which pulley fit those BMW body parts numbers given the number of failures he must deal with.  He did seem to suggest that the existing pulleys either couldn't be re-used or had to be worked on.  My mechanic seems just to have ordered the Beemerbits pulleys, shaftless.  If I do need the shafts I can order them.  My thinking on the plastic pulleys is that, at 46k miles, they'll last me for the life of the bike, or at least another 50k.  Approaching $1300 already, just for tow, rental and gas.  Arghhh.  I just needed to take a decent trip after this awful year, and was so enjoying it. Until I wasn't.

jackronner wrote:Pics of a body offered for sale, showing both sides, with those numbers and the appropriate part number ending with 5323, 5324 for each side.

Agreed, this is a LHS throttle body.

Thanks yet again, David, for all your efforts.  And for enduring all my bootless cries.  Next time, I think I'll finally plump for AAA (the U.S. auto club) dues which might've covered my towing expenses (if they don't just tow you to the nearest town or garage).  Penny-wise, pounded (!) foolish.  I'll let you know how it turns out.

Is BMW Motorrad Roadside Assistance and Insured Warranty available in the US.