Throttle friction remedies?

[dan cata]

Hi all,

 

A friend of mine from over here has an R1150 Rockster. Dunno the year, but I guess it's past 2002, the bike has the servo whining

 

Anyway, he wants to do some mentenance on the bike this spring. Among other small stuff, he also wants to fix his handle acceleration, it works really hard.

 

I never had to deal with the splitter box setup before, and was wondering where the problem could be. Assuming that there is no cable blocked by the fuel tank or anything, I am guessing it's the splitter box fault.

 

Is there any other thing that can cause this? And if it's the splitter box, is there anything that can be repaired or a new one is mandatory? Do cables also have to be bought? A link/tutorial on this issue would be great, and if there isn't any, I'll try to make one when working on the bike

 

Thanks,

Dan.

[AndyS]

A trapped cable would be a first guess.

How about bad routing around the steering head?

Twist grip rubber fouling the switch housing or even the bar end weight causing freedom of movement problems?

Splitter box full of crud,

Frayed cable (could be any one of the cables)

Maybe someone has tried to oil the bowden cables. Becuase the cables are PTFE lined, the oil actually atracts dirt and makes cable stiffer.

After checking the obvious - if it were me, I would consider some dry PTFE based lubricant, as recommended for push bike cables.

Andy

[dan cata]

So Andy, what you are suggesting is to open everything up and inspect/clean and re-assembly?

 

One thing is not clear to me: if I take the tank off, how hard is it to get to the splitter box? How does that one come off?

 

Dan.

[wingnut]

Problem is most likely worn out throttle cable and/or gunk/dirt in the twist grip. My recommendation:

 

1. Replace all 4 throttle cables: main, left & right TB, and fast idle (choke) cables.

2. Disassemble, clean & lube twist grip.

3. Disassemble and clean "splitter" box.

 

I performed the above on my 02 RT at approx 40K and this solved my "hard to twist" throttle problem. Note: I purchased a new Bowden (splitter) box prior to above and did not use it as the original was fine after cleaning.

 

I would also check the throttle butterfly action to ensure a smooth rotation and return.

[dan cata]

Got it.

 

Just curious... Does the spindle on the pulley inside the box wear? Like on the TB's?

 

Dan.

[Selden]

I agree with wingnut -- if you're going to all the trouble to get to the splitter box, replace the cables, and pay attention to routing.

[dan cata]

Just checked with MotorWorks and the prices seem right. It's worth to change the cables as I am in there. For some reasons, I remembered that the price for the same stuff @ the dealer is a small fortune. It might still be, but MW rock!

 

Dan.

[wingnut]

dan cata,

 

The spindle wheel inside the box doesn't rotate very far - guessing maybe 90 degrees. My old one appeared and rotated like new after cleaning. The Bowden box should slide out to the right (starboard) side after bending a metal frame tab up out of the way. Take care with routing the new cables.

[dan cata]

I guess routing will be the same as the cables now on the bike. It only has 34k km's and I doubt that someone messed with them at such a low mileage

 

Dan.

[Michaelr11]

Does he have a Throttlemeister? These can be set too tight and make the throttle movement very heavy, especially when heated grips are turned on.

[dan cata]

No, but he is considering to buy some Wunderlich risers.

 

I know it doesn't have anything to do with the cruise control

[kmac]

I like to work backwards on stuff like this. That way you isolate the problem. You can always just throw new parts at things and likely fix it, but knowing WHY is important to me.

 

I would disconnect at the TBs and move the butterflies {as suggested already}. If those are good, keep moving upstream until you find the tight part. Get all the way up to the twist grip and you will know right where the issue is.

 

I have had bikes where the throttle cable just jumped off of the wheel in the twist grip and was binding up some in there. Easy and free fix, then you KNOW what it was and the fix if it ever happens again.

[NeilCW]

I just had this problem with my new to me 2002RT, hand was tired from trying to twist the throttle. I checked the grip and the butterflies, they were fine. I just sprayed some dry lube graphite in the cable at the grip and it is now easy to turn the throttle.

[dan cata]

I like to work backwards on stuff like this. That way you isolate the problem. You can always just throw new parts at things and likely fix it, but knowing WHY is important to me.

 

I would disconnect at the TBs and move the butterflies {as suggested already}. If those are good, keep moving upstream until you find the tight part. Get all the way up to the twist grip and you will know right where the issue is.

 

I have had bikes where the throttle cable just jumped off of the wheel in the twist grip and was binding up some in there. Easy and free fix, then you KNOW what it was and the fix if it ever happens again.

 

Sounds like a plan

 

Dan.

[AndyS]

Hi Neil, welcome to the group. I hope you stick around, as more heads are so useful on groups like this.

 

Andy

[NeilCW]

Thanks Andy, I hope I can contribute but I think I will be asking more questions than answering

[SAAB93driver]

I found that installing new throttle cables fixes the stiff throttle problem on 2 different bikes. On both bikes around 30-35K miles throttle actuation started to get noticeably stiffer and didn't have a smooth action anymore. (All you have to do is go to a dealer and twist the throttle on a new one to feel the difference).

 

I've never replaced the splitter box, just cleaned it thoroughly.

 

Also never replaced the fast idle cable.