Throttle Position Sensor Help

[jimbo9867]

My recently purchased 2005 Rocket has developed a problem that sounds like a throttle position issue. I purchased the bike with 10,000 miles on it back in February and have since put on another 4,000. A couple of weeks ago I noticed while cruising along at about 2500 rpm it started to feel like it wasn't holding a steady rpm, like it was "searching" for where it wanted to be. Then a few days later I noticed the idle wasn't steady. It might idle at 600 rpm or it might be 1200 rpm. Then after that I was out riding and let off the throttle and lo and behold it didn't slow down. That was a little unnerving at 70 mph. After reading some threads on this forum it sounds like a not uncommon problem for older models and most people seemed to think it's a TPS issue. Anyone here care to share their thoughts? Any help is much appreciated. Does anyone know of a good Rocket mechanic in the sourthwest Ohio are? By the way, I've been riding over 40 years and I've never had a bike I'm as crazy about as the Rocket. What a machine!

 

[warp9.9]

before you go thru the trouble of finding someone to change your Primary TPS try this. on the right side under the tank you'll see two coils the front one is cylinder 2 the rear is 3. Pull the low tension leads off the coils and squeeze them a wee bit with needle nose pliers so they are good and snug going back on the spades. These are the little wires that plug into the fronts of the coils not the plug wires. Pictured below is #2 coil.

after you do this take her for a ride and see if it is any different. #1 coil is up front right under and in the neck area. If you do not have a modified air intake it will be a wee bit more of a pain which is why I say try the easy ones first. also spray copious amounts of WD40 on all the springs one the throttle bodies.
notice them below next to the balancing screws and there are some on the front also right behind the cables.

below has the springs in the front marked as well as the rubber boot on the stepper motor. it pulls down and the WD40 straw fits in well give her a couple blast.

and well yours is a 05 and myself I would change all the vacuum lines and plug caps be careful with the junction nipple where the tree throttle body hose hook to the map sensor hose its a plastic nipple.

 

[jimbo9867]

before you go thru the trouble of finding someone to change your Primary TPS try this. on the right side under the tank you'll see two coils the front one is cylinder 2 the rear is 3. Pull the low tension leads off the coils and squeeze them a wee bit with needle nose pliers so they are good and snug going back on the spades. These are the little wires that plug into the fronts of the coils not the plug wires. Pictured below is #2 coil.

after you do this take her for a ride and see if it is any different. #1 coil is up front right under and in the neck area. If you do not have a modified air intake it will be a wee bit more of a pain which is why I say try the easy ones first. also spray copious amounts of WD40 on all the springs one the throttle bodies.
notice them below next to the balancing screws and there are some on the front also right behind the cables.

below has the springs in the front marked as well as the rubber boot on the stepper motor. it pulls down and the WD40 straw fits in well give her a couple blast.

and well yours is a 05 and myself I would change all the vacuum lines and plug caps be careful with the junction nipple where the tree throttle body hose hook to the map sensor hose its a plastic nipple.

Warp,
many thanks for the very detailed information. I will try this before I take it to a shop. This bike sat in a garage for a long time before I purchased it so I'm sure there is some corrosion on contacts and some drying out rubber parts.

 

[1K9]

before you go thru the trouble of finding someone to change your Primary TPS try this. on the right side under the tank you'll see two coils the front one is cylinder 2 the rear is 3. Pull the low tension leads off the coils and squeeze them a wee bit with needle nose pliers so they are good and snug going back on the spades. These are the little wires that plug into the fronts of the coils not the plug wires. Pictured below is #2 coil.

after you do this take her for a ride and see if it is any different. #1 coil is up front right under and in the neck area. If you do not have a modified air intake it will be a wee bit more of a pain which is why I say try the easy ones first. also spray copious amounts of WD40 on all the springs one the throttle bodies.
notice them below next to the balancing screws and there are some on the front also right behind the cables.

below has the springs in the front marked as well as the rubber boot on the stepper motor. it pulls down and the WD40 straw fits in well give her a couple blast.

and well yours is a 05 and myself I would change all the vacuum lines and plug caps be careful with the junction nipple where the tree throttle body hose hook to the map sensor hose its a plastic nipple.

Yeah!! That squirt in the right places is part of the TPS adjustment. After my R3 TOR/Cat delete / RamAir / HansO Tune / mods the bike continued to have hesitation at low throttle settings, under slow acceleration. After trying Warp99 procedure this AM, went for a ride and, voila! Problem abolished.

"If you do not have a modified air intake it will be a wee bit more of a pain which is why I say try the easy ones first.
Spray copious amounts of WD40 on all the springs on the throttle bodies. Notice them below next to the balancing screws. There are some on the front also right behind the cables. Below the springs in the front marked as well as the rubber boot on the stepper motor. It pulls down and the WD40 straw fits in well give her a couple blast." The blasts inside the boot of the stepper motor was the deal maker for me.

 

[jimbo9867]

Yeah!! That squirt in the right places is part of the TPS adjustment. After my R3 TOR/Cat delete / RamAir / HansO Tune / mods the bike continued to have hesitation at low throttle settings, under slow acceleration. After trying Warp99 procedure this AM, went for a ride and, voila! Problem abolished.

"If you do not have a modified air intake it will be a wee bit more of a pain which is why I say try the easy ones first.
Spray copious amounts of WD40 on all the springs on the throttle bodies. Notice them below next to the balancing screws. There are some on the front also right behind the cables. Below the springs in the front marked as well as the rubber boot on the stepper motor. It pulls down and the WD40 straw fits in well give her a couple blast." The blasts inside the boot of the stepper motor was the deal maker for me.

1K9, after I read your comments yesterday I went back to re-read warps post. The one thing I missed was spraying inside the boot on the stepper motor. Lo and behold after I did that (queue hallelujah chorus) I took it out for a 40 mile ride and it ran like a champ. Thanks to both of you for your comments.

 

[1K9]

1K9, after I read your comments yesterday I went back to re-read warps post. The one thing I missed was spraying inside the boot on the stepper motor. Lo and behold after I did that (queue hallelujah chorus) I took it out for a 40 mile ride and it ran like a champ. Thanks to both of you for your comments.

Ride on Brother. These Brit bikes require frequent tweaking. It's a Zen thing well worth the effort.