garrett's tuning/dyno thread

[gamorg02]

oh most definitely, but like i said this was JUST for WOT in 5th gear. i gotta imagine cruising or not WOT would change it a bit, not sure if the gear would tho.

 

[gamorg02]

well made it the 250 miles uneventfully.

mpg tests:

my first tank i got about 36mpg. that was cruising about 75 - 85mph, limited wrist spasms.

second tank was 33.5 mpg, that was cruising 80-90mph with quite a few wrist spasms, with several jaunts up to 110 and a couple up around 120.

oh and sean, i did a similar ride (210) miles on a stock seat in june. HUGE ******* DIFFERENCE. thanks again for the seat!

 

[one2dmax]

You are welcome,

Sean

 

[RagingMain]

watched a full WOT run with the airlid off the carbs. watched once the slides were completely open.

its obviously not perfect, but +/- 5-10%.


it actually came about b/c he was saying it was all mains at 3.5krpms and i said i though *** was closer to 5.5k or 6k. he said well lets find out.

now this was a 5th gear WOT run, so it might be slightly different for other gears (maybe?) but just a guide maybe?

How could you tell the mains were kicking in just by watching down the carb??? What exactly where you looking at or looking for???

 

[one2dmax]

The best way would be to see the slide pull out and watch the RPM that they finally get all the way out. The airbox being removed will hinder accuracy but still gives you an idea.

Sean

 

[Birdoprey]

How could you tell the mains were kicking in just by watching down the carb??? What exactly where you looking at or looking for???

Looking for when the slides are all the way open. That is when the needle is completely out of the main jet

 

[Birdoprey]

Oops, Sean beat me to it...

 

[RagingMain]

Looking for when the slides are all the way open. That is when the needle is completely out of the main jet

Oh ok, I thought there was more to it than just the slides being all the way out, as in air flow, vacuum, engine load etc. Thanks.

 

[Birdoprey]

Oh ok, I thought there was more to it than just the slides being all the way out, as in air flow, vacuum, engine load etc. Thanks.

You were on the right track. Vacuum/engine load determine when the slides open and how quickly. The result of all that is when the slides are open all the way. When that happens your in your main jetting(well about 90% of the fueling is from the mains. IIRC the pilot jetting is responsible for around 10% even at WOT w/ slides open)

 

[RagingMain]

You were on the right track. Vacuum/engine load determine when the slides open and how quickly. But simply to see when your on your main jetting, just watch the slides.

Cool, have a dyno appt on Tues to see where the bike is after the new cams. Have it pretty well dialed in with your meter, still running a bit lean just cruising around but want to record a few runs using your meter. GF said there is definately more acceleration than before. Back on track

When I get mine dynoed tues I will have to see if the tech will let me watch the slides and record the RPM. Tech is cool, owner is a ****** bag.

 

[Birdoprey]

Cool, have a dyno appt on Tues to see where the bike is after the new cams. Have it pretty well dialed in with your meter, still running a bit lean just cruising around but want to record a few runs using your meter. GF said there is definately more acceleration than before. Back on track

When I get mine dynoed tues I will have to see if the tech will let me watch the slides and record the RPM. Tech is cool, owner is a ****** bag.

Cool deal. Keep us posted!

 

[gamorg02]

well made it back and met up with danny for a bit on the way back thru....

its def not 100% where it was when i left, esp in the top end. not sure if the crabs fell out of synch or something, but gonna mess with it this week. i could easily get the front end up going from 1st to second when really running it beforei left, but now it won't budge when i do the same. i'll do some more tests this week. as danny said, probably wouldn't hurt to get some new plugs as well.

danny's bike is an '06 with 9k miles on it, marks pipes and needles shimmed.

4th gear/5th gear 4k rpms and WOT both bikes are even.
2nd gear, 30 mph, WOT, mine was about a length faster up to almost 4th gear redline.

i'd expect more out of mine having a jet kit on top of the exhaust. this was all done with vboost kicking in @ 3k rpms (where i made the most hp/tq)

 

[gamorg02]

i think i need to drop my mains to 160. bike pulls harder right after its warmed up at WOT, more i run it, the less the front end wants to come up (thats kind of my butt o meter) haha..

i've heard pretty normal with stage 7's to have to drop one...

question is tho, should i keep my mains at 162.5's and try out the stage 1 needles

or

change the mains and keep the stage 7's. i'm not sure if the cruise and midrange and cruise in midrange is rich at this point....

 

[[email protected]]

I don't have any experience with the stg 7's Garrett but from hearing alot of others setups with the stg 7 needles I wouldn't be surprised if you could drop the mains even more than 160's. Didn't you say your elevation was right around 400' or so? I would think 155's would be possible. Mark said he has 152.5's in and he is around 800'. Not sure of the posters name who you were responding to about the needles and stuff but he was 800' elevation and had 155 main. Both had stg 7 needles. That is just two off hand right now.

I was hoping to get a better response to my "survey says" thread in the carb tuning forum. I thought it would help a lot of people get a ballpark idea of where they should be with their carbs when they go about major changes. I just think it would be cool to be able to have a thread like that as a resource. Say you go out and buy some cobra's. You could read that thread and search cobra's to see what jetting is working at what altitude for folks with those pipes. And so on with Sean's kit or stg7.....

 

[gamorg02]

I don't have any experience with the stg 7's Garrett but from hearing alot of others setups with the stg 7 needles I wouldn't be surprised if you could drop the mains even more than 160's. Didn't you say your elevation was right around 400' or so? I would think 155's would be possible. Mark said he has 152.5's in and he is around 800'. Not sure of the posters name who you were responding to about the needles and stuff but he was 800' elevation and had 155 main. Both had stg 7 needles. That is just two off hand right now.

i follow...

I wonder if I should try like something a few steps lower and increase until any stumble is gone. not sure yet.

Are Sean's Mains dynojet or mikuni numbered?

i may also try leaning out my needle until it stumbles at cruise again and then richen until it goes away.

I was hoping to get a better response to my "survey says" thread in the carb tuning forum. I thought it would help a lot of people get a ballpark idea of where they should be with their carbs when they go about major changes. I just think it would be cool to be able to have a thread like that as a resource. Say you go out and buy some cobra's. You could read that thread and search cobra's to see what jetting is working at what altitude for folks with those pipes. And so on with Sean's kit or stg7.....

i love the idea, i think a threaded discussion is a bad medium for it. I think a spreadsheet would be best so people could sort by what they wanted. I wonder if there is a way to do this on the forum.

 

[gamorg02]

what else is interesting, is that the dyno, does show the a/f being rich up until about 7k there then it goes lean, hoping a leaner main wouldn't make that worse? not sure how much a main could skew the a/f line....?

 

[4gasem]

Seans are Mikuni... I run 155's with stock needles shimmed one and stage 7 springs with stock slides. (not drilled)

Runs flawless from low to high but I could probably go down one on the mains.

To lazy to do it and it runs OK.

Chris

 

[gamorg02]

Seans are Mikuni... I run 155's with stock needles shimmed one and stage 7 springs with stock slides. (not drilled)

Runs flawless from low to high but I could probably go down one on the mains.

To lazy to do it and it runs OK.

Chris

how do u know u could go down one on the mains?

 

[4gasem]

Dyno A/F reading... Plus it smells a bit rich. Nothing major though. That's why I left it alone. Plus I am 500 feet below where I tuned it, which isn't much I know...

Chris
needing a home town dyno session.

 

[gamorg02]

can i see your chart? what a/f ratio are you considering rich? and at what rpms?