Throttle Problem after TPS re-install etc

[Ron from BC]

'02 1150GSA

Just installed Dan Cata's Throttle Body Kits (both). I positioned the TPS as closely as I could to the pre-rebuild spot. After getting an initial 1.06v reading and fiddled around until it was .36v. Pulled the Motronic Diagnostic Plug fuse for a minute then turned the ignition and cranked the throttle 3 times.

The bike started immediately and the Throttle Bodies were nice and quiet (Thanks Dan )

Needless to say some other adjustments were needed so after a brief ride to get it up to temp I synced the cables and the bodies and off for another test ride.

Results:

Bike idles nicely at 1100rpm and at speed pulls nicely. The problem is at the point when I just start to move at low rpm from a stop or slow turn. It was faltering and I had to give it more throttle or it would certainly die. Again this is just at that low rpm from about 1200 to 2k.

When I got back I checked the cable sync and throttle bodies with a manometer and they were both good. From the 1100rpm idle in neutral I just slowly rolled on the throttle to replicate my earlier problem only in a stationary position. When it got to 2k rpm it stalled. Now had I throttled up more quickly it would have made it through that problem area.

So......someone kick me in the right direction for this glitch.

Thanks in advance..

 

[Ron from BC]

Follow up

Everything was fine prior to me putting the bodies back on etc with no change to the CCP etc. I've been reading for hours now and what I'm coming back to is "do I have slack in the throttle cables?"

The right cable had sufficient slack and the lock nut is about mid point on the threaded portion of the cable adjuster. When I reconnected the left cable I did have difficulty in getting 'any' slack and in fact threaded portion is screwed in to the max with the lock nut touching the knurled ferrule.

Sitting here now I'm trying to figure out why I don't have more than enough slack with it screwed all the way in. Can this lack of slack cause this low rpm stall issue?

 

[(RIP) DitchWater]

Ron. It is unlikely to be a cable fault unless it is snagging. I would be rechecking your TPS settings and the throttle body balance across the rev range.

Did you move the butterflies in the throttle body by any chance?

 

[red1]

Ron. It is unlikely to be a cable fault unless it is snagging. I would be rechecking your TPS settings and the throttle body balance across the rev range.

Did you move the butterflies in the throttle body by any chance?

The butterflies are swoped to the new spindles with Dan's kit.

Have you checked that the cables are seated correctly in the spaghetti junction box under the battery tray?

 

[Ron from BC]

Ron. It is unlikely to be a cable fault unless it is snagging. I would be rechecking your TPS settings and the throttle body balance across the rev range.

Did you move the butterflies in the throttle body by any chance?

Thanks for the response....everything inside the bodies are fine. I'll recheck the TPS voltage this morning.

 

[Ron from BC]

The butterflies are swoped to the new spindles with Dan's kit.

Have you checked that the cables are seated correctly in the spaghetti junction box under the battery tray?

Hrmmm, I didn't go anywhere near the bowden box so I can't see how they would have moved. It is weird that the left cable had to be screwed all the way down and even then there really isn't much slack.

The bike has 97K miles with the orginal cables so if anything you'd expect them to be stretched a bit and unscrewed having more thread exposed instead of the other way around.

 

[red1]

Hrmmm, I didn't go anywhere near the bowden box so I can't see how they would have moved. It is weird that the left cable had to be screwed all the way down and even then there really isn't much slack.

The bike has 97K miles with the orginal cables so if anything you'd expect them to be stretched a bit and unscrewed having more thread exposed instead of the other way around.

That's what made me suggest the Bowden box. The outer goes slack when you disconnect the TB and could have slid out of the box. I know it took me a couple of tries to get my l/h cable seated when I changed it.

 

[Ron from BC]

That's what made me suggest the Bowden box. The outer goes slack when you disconnect the TB and could have slid out of the box. I know it took me a couple of tries to get my l/h cable seated when I changed it.

Ok...I'll have a look. Please tell me the tank doesn't have to come off..haha. Can I lift it up high enough to see through the left side?

 

[(RIP) DitchWater]

If you need to check the cables you will more than likely have to remove the tank and lift the battery box unless you can get enough light in there and use a long dental mirror to inspect the cable ends to ensure nothing is out of place.
Personally I don't think that's achievable and you're going to have take it all off again to be really sure. One the other hand it could be blatantly obvious if you try and move the sheath by hand and judge how much it moves.

It's painfull working on motorcycles isn't it?

 

[Ron from BC]

Solved!

Well I went out the shop first thing and took the throttle cable off the throttle body and carefully re-installed it. The cable was feeding onto the pulley but it's possible the underside cabling and the end stud weren't seated exactly where it should have been.

I did get some slack so I adjusted it for about 1 mm.

When I had put the TPS back on the TB, post rebuild, I did the initial adjustment and got it at .36 v. Of note, the TPS wasn't positioned anywhere close to where it had been prior to removal for rebuild. So I pulled back the boot and re tested the TPS and got it at .36 v.

After the fuse removal/throttle crank blah blah I started it up and took it for a spin. When at working temp I started to some slow speed turns and starts etc and my stall/falter problem was Gone!!

So whether it was the cable or the TPS or a bit of both it's fixed. I did the cable and TB sync with the manometer and it's running as smooth as silk......phew! I wasn't relishing getting into the Bowden Box to see if the left cable had unseated there.

Thanks to those who replied and kicked me in the right direction!

 

[(RIP) DitchWater]

Well done Ron.

I hope it's not too cold over there.

 

[Ron from BC]

Well done Ron.

I hope it's not too cold over there.

Here in Victoria, it's sort of like the banana belt. 'If' we get snow it usually only lasts days. Rain is another story...lol, my bikes stay insured all year.