Stiff throttle..

[Hamie]

Just got a new-to-me '02 R1150RT yesterday.. tried searh looking for a fix for the stiff trottle.. but didn't find anything.. is the stiff throttle normal for this model and if so is there a way to releave some of the tension? Thanks in advance...

[Ghanziang]

I just got a new to me R1150RTP, and it has a really stiff throttle as well. Hoping there is a solution to this as well.

 

G.

[Joe Frickin' Friday]

If you mean "stiff" as in "stiff spring," well, there's not much to be done about that.

 

If you mean "stiff" as in there's a lot of friction in the cable, aye, that can be fixed. You'll need to replace the main throttle cable from the grip to the junction box under the fuel tank.

 

Some disassembly of the bike is required in order to swap out the cable, including removal of the fuel tank. Since the bike is new to you, I'd suggest checking the Ride/Event planning forum for a Tech Daze happening somewhere in your vicinity. You'll find people there who have had the bike torn to pieces (and probably someone who has done this very job) and will be able to advise and assist you as you take on this job yourself; all you need to do is show up with replacement parts and a can-do attitude.

 

OTOH, if you're all thumbs when it comes to mechanical maintenance, your local dealer will be happy to take care of this for you.

[awagnon]

I guess it's safe to assume you don't have a throttle lock that's partially engaged? Does the throttle snap back when you let it go? Here's a link to a good seminar on BMW Throttle Cable Basics which covers the replacement of an 1150RT cable. It isn't difficult except the actual pulling of the Bowden box out the right side. May have to bend the bracket for the fuel pump plug.

 

http://bavarianmotorcycleworkshop.com/tech-articles/throttle-cable-seminar-for-bmw-motorcycles

[awagnon]

I forgot to mention. I believe there is a new, improved throttle cable for your bike. I may be wrong, but check with your shop. Also, if you replace the throttle cable, save the old one for a spare. I carry my old one after a friend broke his RT's throttle cable on a trip leaving him stranded. ( If you carry a spare, it guarantees the part won't fail. )

[ElevenFifty]

Try the throttle on a couple of other RT's ... They are all a little stiff IMHO. Maybe heavier springs to compensate for the friction in the Bowden box??? I use a throttle rocker - rotate it out of the way when I'm playing in the twisties. That and a throttle meister get me through long highway days.

[Joe Frickin' Friday]

I forgot to mention. I believe there is a new, improved throttle cable for your bike. I may be wrong, but check with your shop. Also, if you replace the throttle cable, save the old one for a spare. I carry my old one after a friend broke his RT's throttle cable on a trip leaving him stranded. ( If you carry a spare, it guarantees the part won't fail. )

 

I've heard this advice for throttle cables, alternator belts, and some other items, i.e. keep the old one as a spare. THe thing is, if you do end up using that old cable during a roadside repair, then you will have installed a crappy, worn-out throttle cable that you didn't want in there in the first place. Sure, it'll get you home, but then you will end up tearing the bike apart to get it out and install a brand-new one to get you back to a healthy, frictionless cable again. I don't enjoy doing repairs twice; I do keep spare parts with the bike for roadside repairs, but they're all brand-new parts.

[dirtrider]

 

Morning Hamie

The BMW oilheads do seem to have pretty stiff throttle return springs. Problem is: with the engine having 2 separate throttle bodies and each throttle body having it’s own return spring with only a single cable running to each that spring pressure adds up quickly.

 

Assuming your throttle stiffness is normal for that series of bike then you will get used to the heavier throttle as time goes by. As mentioned above a throttle rocker or wrist assist can help greatly as your palm takes some of the spring load.

 

Now lets assume your throttle effort is higher than it was when new. Your throttle cables are Teflon lined so you never want to oil them with any type of petroleum based lubricant.

 

I very seldom find the cables themselves being the problem with a heavy throttle feel on the BMW oilhead bikes. The usual cause is excess drag or friction between R/H twist grip and the bar underneath. Sometime the drag is between the twist grip outer end and the end cap (especially if it gets worse with eth grip heaters on). Next place for excessive drag is in the boden box (the box where the cables split and go to the TB units) but that is a REAL pain to access and service so save that till last.

 

So my suggestion is to start by lubricating the R/H twist grip between the bar and grip barrel with something non harmful to plastic (I really like Tri-Flow but any of the Teflon based lubes will work wonders here). I’m guessing this will make your throttle acceptable to you. At least it’s the place to start. If still too stiff then look for cable routing issues or crud in the boden box. To better lube the R/H twist grip to bar simply remove the bar end weight.

 

 

 

 

 

[Hamie]

Thanks for all the replies...I think it is working alright just stiff springs..snappy return.. I did lubricate between trottle grip and bar as suggested by Dirtrider..everything smooth just stiff and I'll will get accustomed with it...Thanks again..

[Quinn]

You can also just fatten up the grips for a better mechanical advantage.

 

----

 

 

[NeilCW]

When I first got my 2002 RT the throttle was terrible, worse when the heated grips were on. I ended up getting non petrolium lube and injected it on the trottle end of the cable with a cable lube tool. Completely fixed the problem.

[Hamie]

You can also just fatten up the grips for a better mechanical advantage.

Put about 100 miles on it this morning...think the throttle is going to be ok... I have grip puppies on order... have been using those for a few years...

[Joe Frickin' Friday]

When I first got my 2002 RT the throttle was terrible, worse when the heated grips were on. I ended up getting non petrolium lube and injected it on the trottle end of the cable with a cable lube tool. Completely fixed the problem.

 

I recall a similar problem, in which I determined that the throttle grip/brake lever assembly was clamped to the handlebar too close to the bar-end weight. Things were OK when cold, but the grip heat caused the plastic core of the throttle grip to expand lengthwise, causing it to bind slightly against the bar-end weight. I solved the problem by moving the throttle grip/brake lever assembly inboard a smidge, so that even when it was hot, it wouldn't bind against the weight.

[awagnon]

I do keep spare parts with the bike for roadside repairs, but they're all brand-new parts.

 

Mitch,

 

I carry my old alternator belt and main throttle cable plus a new sight glass. I figure the odds of using any of these is so remote, I can't justify the cost of carrying new ones (except the sight glass). Also, if I have to make a road-side repair, even with new parts, I'll probably want to do again anyway when I get home to my shop under better conditions. To each his own....