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Can't get throttles balanced

2K views 17 replies 6 participants last post by  AndrewGMoto 
#1 ·
I've got the dealertool hooked up, and I can't get the throttle bodies balanced. I can get two of them, 1 and 2, 2 and 3, but not all three. Any help?

I also have to keep switching com ports to get it to show the readings for the Throttle Balance.

Frustrated.
 
#4 ·
Did you mess with the middle one? Never mess with the middle one. It's the one you balance 1 and 3 to. There's a specific vacuum level the bike will idle and run best at with the throttle closed and if you change the middle one you lose the reference point for that level. If needed I can look up the proper level from my school notes.
 
#5 ·
I put them back where they were, the two screws, and closed up shop. I think they were 68-72-70 (1-2-3). However, now with the throttle closed, the idle will hang around 2k, settle into ~1250, and bobble back up to ~2k. It keeps doing this. Suggestions? I'm almost positive all I made adjustments to were the 1n3 TB adjuster screws. Why it's idling weird, I don't know. But the bike runs great otherwise. No surging, etc. Only at idle.
 
#7 ·
It's possible the idle just needs time to readapt. Try a 12 minute tune. Typically the cause for higher idle however is that the screws are too far open.

Synching isn't just about making each throttle body have equal vacuum to each other it's also about moving the actual vacuum to the proper level overall. Many people miss that last step.
 
#8 ·
I was planning on doing the 12 min adaptation first. Like I said, every time I blip, it'll hang ~2k for a bit, then drop to proper idle for a bit, then move back up to ~2k. When it does drop to idle, it's at ~1250, where it should be.

Nother quick question: what can I do about stripped screw holes in the airbox? One hole on the side and the screw holding the MAP sensor on the LH side of the airbox are stripped. Still work, but cheap screws in plastic, c'mon Triumph... I think whoever took the airbox off last gave them a little too much muscle.
 
#11 ·
Thanks, mate. Will do.

I did a 12 min adapt tune, and it still hunts between 2k and regular idle. It didn't seem to hunt when I did the adapt. However, when I rode it later on, it was still hunting. I'll check that the hose on the MAP sensor is connected and see if everything is kink free under the tank.

Sometimes I wish these things had idle adjuster screws...
 
#12 ·
Checked the MAP sensor. Connected at both ends.

However, I did notice my throttle cable used to have a little play in the grip before engaging. Now, it seems to have almost none.

Perhaps this is "confusing" the bike as to whether it is or isn't in a true idle state.

Possible?
 
#13 · (Edited)
You should be able to hear (at lower end of cables) the throttle stop hit full open when you twist the grip and hear the stop hitting full closed when you reverse twist the grip.

If you can't hear the closing click, adjust pull closed cable until you can....which will also give a little free play to the grip.
 
#14 ·
Question:

If my throttles are not balanced, does riding at highway speeds cause any damage to the engine?

I haven't had a chance to get the TB's balanced yet, but would like to take the bike an hour outside of town this weekend. I haven't been riding it lately due to the TB's needing balanced, but still want to take it out this weekend.
 
#18 ·
Nyeah, I can't get the dealertool software to keep a connection long enough to match all three cylinders. But two match, and one is slightly off. After attempting it twice, I said fk it, and will bring it to a dealer. Haven't had the spare coin lying around to do that yet.

Since I adjusted the valves, even with the TB's not balanced, I've noticed the bike is smoother already, at highway speeds. It certainly isn't buzzier. It's just got a **** idle. But when you're cruising, everything seems peachy.
 
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