I Needs Throttle Body Advice

[Don M]

I've been doing throttle body syncs and valve adjustments for years on my oil heads without problem so this has kind of shaken my confidence.

 

I currently have a 04 R1150RT with 50,000 miles on it. Just went through the usual tune up steps. I pulled and cleaned the plugs, did a valve adjustment...slight adjustment to one exhaust valve and all four intake valves were so close (left side maybe a smidge looser than the right) that I didn't think I could improve much. I checked the throttle cable rockers for debris. Put everything back together, warmed the engine up and started a throttle sync. I couldn't budge the right BBS and the left screw was very tight. When I finally got the screws out I found corrosion in the throttle bodies above the BBS "O" ring and both screws were heavily coated with a black deposit. I cleaned everything up and got both screws turning easily. I used a very light film of anti-seize on the screw threads and a film of silicon grease on the "O" rings. I haven't done anything with the TB's other than spray a little carb cleaner in the BBS ports and swab them out with a Q-Tip.

 

At this point I can't get the TB's balanced at idle unless they are more than two turns out from each other....in the past I could balance with only a 1/2 turn difference. I haven't even tried a high RPM balance yet

 

I've got new new BBS's coming next week. I'm going to put in new plugs and get more anal about a valve adjustment before I try to do another balance.

 

I'm thinking I should do more about cleaning the TB's...maybe more carb cleaner and some compressed air. I've never removed the throttle bodies and I'm concerned that my inexperience will just create a new variable in the balance procedure.

 

Anyone got any thoughts, advice, ridicule?

[dirtrider]

Afternoon Don

 

A couple of thoughts before tearing the TB’s off or re-doing the valves.

 

First, make darn sure your cables are properly seated their furrels at the TB’s the cables have some SLACK in them at idle.

 

Next make sure your choke is off & not holding the cables tight.

 

Next, remove the BBS screws again & use some 02 & cat safe carb cleaner to clean the air passages under the BBS screws, then blow out the passages using compressed air. Possibly some remaining coke in the air passages or maybe some of that grease you used down in the air passages.