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#304804 - 03/07/08 01:38 AM Throttle body sync  
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Flyer5 Offline
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Flyer5  Offline
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Montrose PA
One thing I dont think I have seen when reading about syncing the TBs is cleaning them . I have my bike torn down for the other repairs ,I was suprised how much coking was inside the tbs . Like it wasn't cleaned in the 100,000miles at all . How can they be properly balanced especially at idle with that kind of build up . I would recomend cleaning them at least at the 25k tune ups . I would bet the idle would improve drastically . Dave


Current rides 2000R1100RT Black
Quicksilver MXL Sport 2 Light sport aircraft
#304805 - 03/07/08 01:48 AM Re: Throttle body sync [Re: Flyer5]  
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Rider1200RT Offline
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FT. Lauderdale
That is the reason why, at a minimum, the brass idle screws need to be pulled out for cleaning before doing a TB sync. This lets the idle speed to be adjusted within spec. Cleaning the entire TB's is ofcourse a better way, but a bit more involved..


Oscar W.
2017 R1200RT
Fort Lauderdale, USA



#304806 - 03/07/08 02:08 AM Re: Throttle body sync [Re: Flyer5]  
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T__ Offline
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Quote:

One thing I dont think I have seen when reading about syncing the TBs is cleaning them . I have my bike torn down for the other repairs ,I was suprised how much coking was inside the tbs . Like it wasn't cleaned in the 100,000miles at all . How can they be properly balanced especially at idle with that kind of build up . I would recomend cleaning them at least at the 25k tune ups . I would bet the idle would improve drastically . Dave




Dave, if you find the right replays in the archives you will see it has been addressed a few times..

As long as you have the bike apart,, cleaning the throttle bodies is a great idea.. As mentioned above the air by-pass screws & seats are probably the important part..

Those TBI units are basically just big air valves so as long as the air let in to the engine is the same side to side at idle & through the operating range a little cokeing shouldnít matter (that is the balance part).. If the cokeing gets too bad you wonít be able to get the correct idle RPM without having the air by-pass screws turned out too far & that should put up a red flag that there is an air flow problem..

Those TBI units donít meter any fuel (only air) so the computer actually meters the fuel using the same pulse width for each side so unless the injectors are plugged it should get the same fuel delivery for each side..

Probably if the cokeing gets bad enough the air flow will be reduced for a given throttle plate opening & that could skew the TPS voltage per liter of air metered but I doubt that would effect the idle as long as the brass air by-pass screws can cover the reduced air flow..

I guess if the idle speed & balance can be obtained with the brass screws near the proper initial setting the cokeing probably isnít effecting much.. If the brass screws need to be opened much above base setting or if off much side to side than cokeing could be an issue..


Twisty

#304807 - 03/07/08 04:25 AM Re: Throttle body sync [Re: Flyer5]  
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NonComp Offline
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The Great White North
Can the TBs be cleaned in place? Can you spray some carb cleaner in them, let it sit for a while and then swab it out? Or...?

#304808 - 03/07/08 12:05 PM Re: Throttle body sync [Re: NonComp]  
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Quote:

Can the TBs be cleaned in place? Can you spray some carb cleaner in them, let it sit for a while and then swab it out? Or...?




Glen, probably but you must be careful as some of carb cleaners could damage the rubber intake boots & will surely damage the bikes paint if it gets on that.. If you do that (clean them in place) make sure the carb cleaner is labeled to not damage your 02 sensor (those are expensive) or damage your cat (thatís catalytic conveter not your house cat)..

You have to pull the air filter side anyway so why not just pull the intake side & throttle cables & get them away from the bike.. If you clean them you will have to do a TBI balance anyways..

Twisty


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