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Ain't it fun!!! Be careful with this kit it hits redline really quick......think I need a shift light:punk:

Dale #2592
 
I put quite a few miles on over the weekend. The bike is running good but still not 100% where it should be. I experience a lean surge when SLOWLY going from 6-7K. Meaning, if I am holding the throttle steady, at a small opening (between 1/8 and 1/4 open) and let it build up revs slowly, is when this is most noticeable. It surges a bit and doesn't want to move past this RPM. At this point it also feels like it does not want to go any more. If I give more throttle, it stumbles a bit and then goes. If I am hammering through the gears and not cruising though, you don't even notice it.

Also notice it still slightly stubles from 5-6.5K but again, only while holding the throttle at a small opening.

I understand these are both lean conditions. I was curious if the 6-7 surge would be a main jet or needle issue?

If it is a main jet issue, I assume I would do just the mains and not add another shim to the needle until I test again, correct?

Current setup is 160 mains, 1 shim on stock needles, stock diaphragm springs, did not drill slides, 1200' elevation.
 
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Easiest to check would be the shims. If that doesn't work or gets worse you go up one main and take shims out and start over in the shim process.

Sean
 
OK, Thanks Sean. Shims are definitely easier.

However, it was not nearly as hard to pull the carbs to do the main jets as I had imagined. A bit time consuming since I've never even taken my air filter lid off before this and wanted to make sure I did things right, but not hard.

If anyone is on the fence about buying this kit because they are afraid to install it. Don't be. There is enough info on this forum to get you through. Not to mention the professional tuning advice after the install from Sean, Mark, and everyone else. :punk:

Thanks guys.
 
Here is the Dyno from Seans Muscle Kit on my bike when it was first built in Topeka.
 

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I just got back from a few rides this weekend, only got about 250 miles in, but my fuel mileage averaged 39.5 mpg, I think I was around 30 before Sean's kit. I also have my v-boost left open from when I swapped components for Abe's bike. No fuel light at 100 miles for me any more:eusa_dance:.. and I was probably averaging 70-75 miles per hour or 4500-5000rpms.

Later,

Jeff
 
Been playing around with carb settings still. I'm feeling pretty good about how its running now. I will leave it alone for a bit and probably get new plugs so I can start clean and see how they look after some miles. Also want to see what the mpg is now.

I am now running 162.5 mains, stock needles with 2 shims, a/f screws 2.75 turns out, 1200' elevation. stock springs, did not drill slides (yet?)

Still toying with the idea of drilling my slides. If I'm cruising around at 4 or 5K and I crack it wide open will drilling the slides and changing the springs help it rev into vboost range quicker? Sorry I keep talking about the slides, LOL.
 
Just got back from another little cruise. I have no idea how in the hell anyone is getting 40+ mpg:ummm:. My low fuel light just came on @86 miles...again. I didn't get gas yet but that will work out to MAYBE 30mpg by the time I fuel up. I just cant get it to do any better than mid 80's till the light for some reason. Seems to be running good. It was lean in the midrange before I added the second shim to my stock needle. It was popping alot and breaking up, sometimes surging right before the main jet kicked in with only one shim.

The main may be rich at 162.5? I don't know. I had the 160 jets in there and it ran ok up top. I don't really ride all the time at 7K+ so I don't see how it would kill economy. I honestly haven't been able to tell much of a difference between the two main jets. Bike doesn't really pull any better/worse up top. I feel like I may not be observant enough or something to some of these things. I just don't notice much, if any difference with alot of the different tuning that I have been trying. The largest difference I saw was when adding shims to the needle.

I just changed from stock to the stg 7 slide springs between rides and I really couldn't feel much of a difference. Maybe my buttometer needs some fine tuning?

I'm not too worried about getting 40mpg as I hear a few mention. I just want to make sure I have the carbs set right so nothing bad happens. Lately, I have not really done any highway riding. Its 90% backroads doing a lot of boosting in lower gears and running up to triple digits whenever I find an open spot. Does this kind of riding kill the mileage that much?
 
Last time I rode, the light didn't come on till 110 miles. I was running 167.5 main jets with two people for about half the tank. Doing hard accelerations and getting into triple digits will definatly burn more fuel than just easy cruising.
 
Hey Mike, You really need to get it on a dyno or at the very least get an A/F reading. Mines pretty dead on and I get over 40 when cruising...
 
Lower gears and constant throttle position changes will eat up fuel very quickly.

Sean
 
Been playing around with carb settings still. I'm feeling pretty good about how its running now. I will leave it alone for a bit and probably get new plugs so I can start clean and see how they look after some miles. Also want to see what the mpg is now.

I am now running 162.5 mains, stock needles with 2 shims, a/f screws 2.75 turns out, 1200' elevation. stock springs, did not drill slides (yet?)

Still toying with the idea of drilling my slides. If I'm cruising around at 4 or 5K and I crack it wide open will drilling the slides and changing the springs help it rev into vboost range quicker? Sorry I keep talking about the slides, LOL.

Decided to remove one shim from the needles and ride it like this for awhile with the same mains. Did a short test run and it feels pretty good. Hoping to get a good ride in here sometime soon and be able to really test out the performance and MPG.
 
Decided to remove one shim from the needles and ride it like this for awhile with the same mains. Did a short test run and it feels pretty good. Hoping to get a good ride in here sometime soon and be able to really test out the performance and MPG.

It is very hard to believe that at 1200 feet you are not running rich with 167s for your mains, if that is Mikuni jets
Have you had a chance to dyno it to check you A/F reading?
 
It is very hard to believe that at 1200 feet you are not running rich with 167s for your mains, if that is Mikuni jets
Have you had a chance to dyno it to check you A/F reading?


Not exactly sure where you saw 167's??

I'm running 162.5's..... I was getting a lean surge around 6K rpm with the 160 mains and 2 shims on the needle. Jumped up to 162.5 mains and kept both shims on for the last month. Ran good but, mileage has been poor so finally decided to get off my ass, clean the bike good, and pull out a shim and see how it goes. So far so good. Only 20 miles in the saddle since the shim removal

I have Mikuni mains, not DJ. I agree that 167.5 mikini's would be pretty large. FYI: current setup at 1200' elev. is 162.5 mains, stg 7 springs, not drilled slides, one shim on needles, 2 3/4" turns out on a/f screws.

If anyone has any suggestions on getting better mileage and performance I'm all ears. I'm reading up on the A/F meter stuff. It sparked my interest long ago when I saw you start a thread about it. I've been thinking about taking the plunge and buying some stuff but I have so many other things I want to do that cost $$$ (not max realted CR500 and GS550) and the max is running good sooooo... IDK what to do right now.

I'm thinking the shim will help with economy. The bike seems to run fine either way. Possibly just a touch more responsive with one shim vs. two.

I'll check mpg after awhile and next time I get bored i'll drop down to 0 shims. I guess I started out backwards cause when I changed mains I should have removed shims and worked my way up instead of down but, too late now :biglaugh:.

EDIT: I have NOT had the bike dynoed
 
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That jet size doesn't surprise me at all. When you have morleys's kit with stock needles you need big mains. Mine wouldn't run in the top end until I got to 170's. That's right.....mikunis! I haven't heard of anyone else using this big of mains but my bike likes it. 800' elev.

I did have 2 shims in the needles. Changed it down to a 3/4 clip shim by paul. Got 39 mpg down to Thunder. But around town I'm more like 32 mpg.

I haven't had a dyno but I would really like to know where I'm at. Plugs look good and pipes have hardly any soot in them.....must be good!:punk:

Dale #2592
 
Just got back from another little cruise. I have no idea how in the hell anyone is getting 40+ mpg:ummm:. My low fuel light just came on @86 miles...again. I didn't get gas yet but that will work out to MAYBE 30mpg by the time I fuel up. I just cant get it to do any better than mid 80's till the light for some reason. Seems to be running good. It was lean in the midrange before I added the second shim to my stock needle. It was popping alot and breaking up, sometimes surging right before the main jet kicked in with only one shim.

The main may be rich at 162.5? I don't know. I had the 160 jets in there and it ran ok up top. I don't really ride all the time at 7K+ so I don't see how it would kill economy. I honestly haven't been able to tell much of a difference between the two main jets. Bike doesn't really pull any better/worse up top. I feel like I may not be observant enough or something to some of these things. I just don't notice much, if any difference with alot of the different tuning that I have been trying. The largest difference I saw was when adding shims to the needle.

I just changed from stock to the stg 7 slide springs between rides and I really couldn't feel much of a difference. Maybe my buttometer needs some fine tuning?

I'm not too worried about getting 40mpg as I hear a few mention. I just want to make sure I have the carbs set right so nothing bad happens. Lately, I have not really done any highway riding. Its 90% backroads doing a lot of boosting in lower gears and running up to triple digits whenever I find an open spot. Does this kind of riding kill the mileage that much?

Pulled a shim off the needles and everything else is the same on my carbs since the above post. Hit the road for a hi-way run. Lots of open road and steady cruising at 70 mph average, mix in a few high speed blasts, and some stops, and I got 41.6 mpg. I'm feeling pretty good about breaking the 40 mpg barrier finally.
 
I have 155's with stock needles and Seans kit. Seems odd that I run that small of a jet when everyone else runs the larger ones. What's really odd is the dyno sheet shows a slight rich condition...
 
we've had them all over the place which is why the kit comes with so many jets to select from.

Sean
 
I bought a Kerker 4-2-1 header and carbon fiber muffler from Sean. I'm thinking about going with the jet kit also, but I was wondering what I could expect for HP increase from what it is now. I currently have stock jetting and intake and it seems to run great, may be a little rich down low. Does anyone have dyno results from Kerker 4-2-1 with stock intake? Thanks.
 

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