TB sync help needed

[BeemerBerg]

Trying to do a TB sync on my 2010 RT, Using GS 911 & simple manometer. But noticed that the TB are off sync at idle (I understand that's not uncommon, and nothing to worry about), but the vacuum between the Left & Right would shift dramatically: at lower RPMs the right would have a higher vacuum, and at higher RPM the Left would be higher. The JVB video says to sync at 3000-3500 rpm, But when doing so, levels above or below that RPM seems to favor either Left or Right. And now the bike runs like crap (should have left well enough alone)

 

 

I also have mercury carb styx and a Twin Max, but all methods seem to show that the TBs are not 'sucking' at the same rate throughout the throttle spectrum.

 

Could something be wrong with the throttle cables themselves?? Maybe the box where the throttle cables join? There doesn't seem to be any leak in the intake manifolds. Yes, there is some slack in the main throttle cable at the throttle twist.

 

Any suggestions??

 

[Bernie]

Good afternoon, Ken.

Make sure you have also slack at the cable adjuster at the throttle bodies. Sometimes the little metal shield on the end of the cable does not reseat itself into the adjuster. Also do not forget to reinstall the hose on the left air tube and the cap on the right air tube, after you remove your hoses for the Twin Max.

Did you first adjust the valves? Make sure you have the wires for the spark plug stick coils properly seated, as the center plugs do all the work above 4000 rpm.

[dirtrider]

Trying to do a TB sync on my 2010 RT, Using GS 911 & simple manometer. But noticed that the TB are off sync at idle (I understand that's not uncommon, and nothing to worry about), but the vacuum between the Left & Right would shift dramatically: at lower RPMs the right would have a higher vacuum, and at higher RPM the Left would be higher. The JVB video says to sync at 3000-3500 rpm, But when doing so, levels above or below that RPM seems to favor either Left or Right. And now the bike runs like crap (should have left well enough alone)

 

 

I also have mercury carb styx and a Twin Max, but all methods seem to show that the TBs are not 'sucking' at the same rate throughout the throttle spectrum.

 

Could something be wrong with the throttle cables themselves?? Maybe the box where the throttle cables join? There doesn't seem to be any leak in the intake manifolds. Yes, there is some slack in the main throttle cable at the throttle twist.

 

Any suggestions??

 

Evening BeemerBerg

 

How far off (inches of water) are the sides through the 2500 to 3500 RPM range?

 

First off, have you moved any adjustments yet? If not then ride the bike a few miles & to get the engine nice & warm & allow the computer to re-learn the fueling.

 

Then-- shut the engine off & hook up your manometer-- then use the twist grip to run the RPM's up to about 2500 & see what you have (don't use the GS-911). Then slowly run the RPM's up to 3500 & see what you have.

 

If only an inch or so of water height difference that is no big deal.

 

If it still varies between sides as you run it up then check the L/H cable where it enters the splitter box to make sure the outer cable is seated firmly into the splitter box. Then look on the R/H side to make sure that he R/H cable is running properly over the air box area.

 

Then check both sides to make sure the cable adjusters at the throttle bodies are not broken in the threaded area.