Capt_Ron Posted March 12, 2007 Share Posted March 12, 2007 I bought this beautiful machine about 3 months ago and I've noticed on a long straight road, it has a definite tendency to drift right. I have to keep very slight pressure on the left grip to keep it headed straight down the road. Does anyone have any idea why it is doing this and what the remedy might be? Thanks. Ron Link to comment
philbytx Posted March 12, 2007 Share Posted March 12, 2007 It's called PTTR....and TADT If you do a site search for PTTR you will see that, just like oil threads, this has been done to death in the past Link to comment
strat Posted March 12, 2007 Share Posted March 12, 2007 mine did that until I shifted my package!!! Link to comment
Joe Frickin' Friday Posted March 12, 2007 Share Posted March 12, 2007 As Philby says, it's PTTR; TADT. We've got a (rather old) FAQ entry here. Lots of theories as to why. Most plausible I've seen so far is a weight bias. I took some rough measurements last fall with an inclinometer that suggested the CG was shifted to the right of the bike's centerline by 1 degree, but haven't double-checked them yet. Will try again one of these days. Link to comment
St_Louis_Don Posted March 12, 2007 Share Posted March 12, 2007 PTTR is normal. It is important to note: moving to the Southern Hemisphere will cause PTTL. Only know remedy is to ride at the Equator. Link to comment
Capt_Ron Posted March 13, 2007 Author Share Posted March 13, 2007 Is the Pull to the Right effect more prominent in the 1100RTs than the 1150RTs? I test drove a 2004 R1150RT the other day and specifically drove some highway miles checking for the PTTR. I didn't detect any drift with this particular bike. Did BMW do something with the later models to minimize this PTTR? Ron Link to comment
chrisolson Posted March 13, 2007 Share Posted March 13, 2007 My '99 didn't have a drift, it was more like a dive. Opinions vary...some very intelligent people say that removing the rear wheel shim is pure bunk....I can only say doing so made a difference for me - didn't eliminate it, but helped. Link to comment
Capt_Ron Posted March 13, 2007 Author Share Posted March 13, 2007 I have a chance to trade-in my 1100RT this week for very nice '04 1150RT. I'm reluctant. I don't especially like the servo assisted brakes on the 1150, but I do like that it drives straight. It doesn't seem to surge any either. My 1100 suffers from that, too. I ordered one of those TwinMax carb syncro gadgets and thought I'd just check the TBS on my 1100 to see where it was at. It had a 60,000 mile service about 1500 miles ago but it still surges quite a bit at about 3500 rpm. I may just have to do a valve adjustment and TBS myself (with some help from a friend) to resolve that problem. Except for the drifting right and the surging, I love everything else about this bike. Ron Link to comment
Les is more Posted March 13, 2007 Share Posted March 13, 2007 mine did that until I shifted my package!!! Yes, I keep a fountain pen in my left side case for just that reason. Sorry, dude--couldn't resist! Link to comment
JATO Posted March 13, 2007 Share Posted March 13, 2007 I cured my PTTR about 7 years ago on my 96 1100RT. I posted it here, but I'd bet no one tried it. Try this easy fix: use stick on weights every 90 degrees around the LEFT SIDE circumference of the front wheel. Start with 1/2 oz every 90 deg, then test ride. If it doesn't help enough, add one more weight adjacent to the others, testride again. Mine took 3/4 oz every 90 deg to eliminate PTTR from 30 mph to 100 mph. Never tested above 100 mph, it may PTTL. It solved the wear on left side of tire problem, AND no longer any cupping worries. 128,000 miles on the bike. This will not effect the wheel balance, and the group of weights will never have to be removed if placed 90 degrees apart. The gyroscopic effect of the weights helps the front wheel stay upright, thus no subconscious countersteering to the left and left side tire wear.------I just used a long enough straightedge through the center of the wheel, then a carpenter"s square to determine the 90 degree angle from that and marked the rim with chalk.--- good luck, Jay Link to comment
Clive Liddell Posted March 16, 2007 Share Posted March 16, 2007 Jay, interesting theory... My partial solution also involves lead weights: Pick up a handful of old car balance weights - around 1.5 to 2 oz and stack them along the base of the glove box. Of course I have no radio. In my case the "bed" of weights does help a lot, even to a tad of PTTL when the asymmetric fuel tank is nearly empty. They also don't affect the volume of the glove box much. Link to comment
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