garrett's tuning/dyno thread

[gamorg02]

garrett's tuning/dyno thread - morley kit install

hey guys. just got the bike back! first impressions:

1. the midrange/low end umf isn't really there at like anything up to 1/2 throttle, where it used to be at like 1/3 throttle. open it up and i'd say it sback but about 1/4 - 1/3 throttle more than it used to be.
2. WOT pulls like a mothafucka.

here is the best dyno graph. open for comments!

info:

sean's jet kit
walker exhaust with 17" cans
400' above sea level i think
today was wicked hot and humid, 90+ plus
a/f screws i guess are all different between 3 and 5 turns out as he said each carb wanted it differently. he shoved his o2 sensor all the way down to get each reading (they were each about 3.5 out when he took them out)
162.5 mains with 1 shim
sean's springs
i don't believe he drilled the slides but could find out

any other info def let me know.

116 seems a bit on the weak side, and i'm not sure what cuases that 6rpm a/f dip, but i'd love to know. he thinks it might be the walker pipe structure? esp the fact the rear pipes are so much shorter than the front.

he said he had fun playing with vboost/tboost/off and definitely seeing vboost by far get the best HP.

other than that he also said he thought he could get the a/f curve straighter with stage 7 adjustable needles but he thinks that 116 is about the most the bike's got at this point.

the guy that tuned its name is Rick Stetson. That name may mean something to some guys here, i guess he won a bunch of drags back in the day. he had a couple drag bikes there and did all the machine work for a 636HP busa with 3xx ftlbs torque. he said it was unrideable in that form.

 

[gamorg02]

oh and i guess it doesn't say it on the graph, but the correction was 1.03 i think?

 

[4gasem]

Looking at it on my phone I'd say that it's going pretty rich right when vboost comes in. Let's see what mark And Sean have to say. 162.5 seems a bit rich but the graph shows otherwise.

 

[maleko89]

You main seems pretty good. Concerned where it goes way rich at the top of your needle range/vboost. I would loose the shim as it seems like it is pretty damn thick. Once that's done I would re-evaluate and do the needle test (4th gear/4K rpms). You may need to put stock springs back in. I find with stage 7 springs that the slides open sooner than normal and faster. Your pilots and up to 4K looks good.

 

[maleko89]

I forgot to mention that your midrange richness could improve on a less humid day. Humidity sucks horsepower.

 

[gamorg02]

Mark, Chris, thanks guys... i actually called sean a few mins ago as he asked me to once everything was installed. he's gonna call me back shortly

anywho.. so i definitely feel not a loss in power, but a flatline from 4k - 5500 rpms, with anything but 3/4 - WOT. is that the needle? prior to the install it would keep growing there, but now, until it hits vboost, i dont notice a an actual accel. unless like i said, WOT. with WOT, holy fucking shit. i had the front end off the ground going into second about a foot and a half the first time i was able to punch it. whoo fucking hoo...

so mark, you're thinking the shim in the needle is actually hurting that range?

also, one other thing. before, if i did say like 1/3 throttle and let the engine keep climbing slowly you would FEEEL vboost kick in about 7500rpms. i dont feel that kick anymore with similar throttle. infact i don't really feel vboost as much anymore even wot, but i'm actually giggling so much its hard to tell.

 

[gamorg02]

I forgot to mention that your midrange richness could improve on a less humid day. Humidity sucks horsepower.

still felt the flatline 10 mins ago. much less humid and only 78 degrees out.

 

[gamorg02]

oh and the slides are drilled. my buddy dropped off the paperwork, since he had it in his car when i picked up the bike

 

[maleko89]

Mark, Chris, thanks guys... i actually called sean a few mins ago as he asked me to once everything was installed. he's gonna call me back shortly

anywho.. so i definitely feel not a loss in power, but a flatline from 4k - 5500 rpms, with anything but 3/4 - WOT. is that the needle? prior to the install it would keep growing there, but now, until it hits vboost, i dont notice a an actual accel. unless like i said, WOT. with WOT, holy fucking shit. i had the front end off the ground going into second about a foot and a half the first time i was able to punch it. whoo fucking hoo...

so mark, you're thinking the shim in the needle is actually hurting that range?

also, one other thing. before, if i did say like 1/3 throttle and let the engine keep climbing slowly you would FEEEL vboost kick in about 7500rpms. i dont feel that kick anymore with similar throttle. infact i don't really feel vboost as much anymore even wot, but i'm actually giggling so much its hard to tell.

What's the shim thickness? Anything more than .020 inches is too thick IMO. With DJ springs slides/needle has major affect from 4000 rpm until 6500 rpms or so. You shim is helping low end and the bottom part of your midrange but it hurts you for the rest of the midrange. That's why it is important to start with the floats and main and work your way down. You don't want to use your needle to tune your low end, etc. I would leave the main alone for now...espeically with it running that good at WOT. With Sean's kit and stock needle I have yet to see one with a smaller main that 162.5's. Personally , I ran 165's with stock needles. You may want to be sure your needles are fully seated. Remember to make sure the spacer nipple drops into the matching slide hole.

Glad you are having fun!

 

[gamorg02]

What's the shim thickness? Anything more than .020 inches is too thick IMO. With DJ springs slides/needle has major affect from 4000 rpm until 6500 rpms or so. You shim is helping low end and the bottom part of your midrange but it hurts you for the rest of the midrange. That's why it is important to start with the floats and main and work your way down. You don't want to use your needle to tune your low end, etc. I would leave the main alone for now...espeically with it running that good at WOT. With Sean's kit and stock needle I have yet to see one with a smaller main that 162.5's. Personally , I ran 165's with stock needles. You may want to be sure your needles are fully seated. Remember to make sure the spacer nipple drops into the matching slide hole.

Glad you are having fun!

not sure what the shim thickness is, they are what comes with sean's kit. i'll have to ask him.

i'm more than happy leaving the main alone.. not something i want to deal with to be honest.

these are stock needles btw.

I assume your second to last sentence means to make sure the needles sits into the jet properly when the slides are closed? and the last sentence lost me. sorry man.

 

[maleko89]

not sure what the shim thickness is, they are what comes with sean's kit. i'll have to ask him.

i'm more than happy leaving the main alone.. not something i want to deal with to be honest.

these are stock needles btw.

I assume your second to last sentence means to make sure the needles sits into the jet properly when the slides are closed? and the last sentence lost me. sorry man.

No worries. I'm talking about making sure the plasic washer with the little tit is flush with your shim/e-clip and also making sure the nipple is seated in the slide. What I do is put the needle in the slide. Then, slowly rotate needle by pointed end while lightly pulling down. It should drop a smidge...that way you know it's seated.

The last sentence was glad you are having fun.

 

[dannymax]

not sure what the shim thickness is, they are what comes with sean's kit. i'll have to ask him.

i'm more than happy leaving the main alone.. not something i want to deal with to be honest.

these are stock needles btw.

I assume your second to last sentence means to make sure the needles sits into the jet properly when the slides are closed? and the last sentence lost me. sorry man.

Garrett...when you pull the needles out of the slide there is a neoprene spacer under the circlip, on the bottom of that spacer is a little tit that fits into a tiny hole in the bottom of the slide.

Pull your slides out and see if you can turn the needle or if it resists. Don't use pliers or anything, if it's not seatet it will prolly turn pretty easy.

Better yet, give me a call if you can.

danny

 

[one2dmax]

Actually, if not seated it will bind up and not have any "spring" feel to it when pushing in. I would suggest to remove the washer as Mark noted and maybe change the springs. To remove richness out of the midrange you can change the PAJ2 (under the diaphram) to the 177.5 jets that were in cluded in the kit.

Sean

 

[gamorg02]

Mark, thanks man i'll take a look!

danny, thanks for answering. good chatting w/ya. got a better idea now what i'm going to be looking @

Sean,
will do. springs are easy enough

one more question. which order should i try things:

would they be:

1. remove needle shim. then try it out, if still flat,
2. put paj2 177.5 in. then try out?

where should i try putting the oem springs back in?

 

[one2dmax]

Do one change at a time. Changing the PAJ2 will make the biggest change but may not be where you want to start.

Try the shims AND springs at the same time however and maybe even first.

Sean

 

[gamorg02]

Do one change at a time. Changing the PAJ2 will make the biggest change but may not be where you want to start.

Try the shims AND springs at the same time however and maybe even first.

Sean

i will do shims/springs. and take it out. i'll post back with results seeing if the PAJ2 change will help. i may be fat dumb and happy with the results.

 

[4gasem]

With Sean's kit and stock needle I have yet to see one with a smaller main that 162.5's.

Glad you are having fun!

That's not true! I have 155's in mine and it runs like a rapped ape! I really noticed a TON of low/mid end grunt over what I had in there previously.

 

[gamorg02]

One more question guys. rode the bike to work today, and won't be able to wrench on it until the afternoon. anyways

the guy who tuned it said it had a lean cruise. i would def agree that there's a flat spot (how to tell if rich or lean i have no idea) when crusing, as it takes a bit more throttle than before to maintain highway speeds. this seems to be the biggest issue during that flatspot, 4500-6k ish...

thats why he didn't remove the shim (i forgot to say before) because the cruise was lean. does this make sense?

 

[maleko89]

Cruise should be tuned with your pilot circuit (PAJ1, PAJ2, mixture screws). If you tune your cruise by adjusting your needle you'll cause issues with your pilot circuit. Dan-o had this same thing due to a too thick of shim. Float levels are important for cruising/pilots too.

 

[gamorg02]

gotcha mark, so (still going to try one at a time) but removing the shim should get rid of the 4-6k rich spot

and moving the PAJ2 to a 177.5 will get rid of the lean in the cruise?

i am also hearing some popping on decel that wasn't there before..