Jets
- Thread starter Gretsch
- Start date
sweatmachine
moped
155s does sound a little big. I would try a range from 140-150.
ivar
TT Racer
Higher elevations = thinner air = use leaner jets than at sea level
Post your mods & current jetting
Myself running TPUSA ARK + Dominator touring pipes, stock needles, 145 mains, 42 pilots. Sea level. Maybe a tad lean on the needles and should have put on 1 shim.
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sweatmachine
moped
how's it running with 140s? I would think at your elevation you'll need between 130-140s. That's just a guess though.
Gretsch
Rocker
Not too bad. It sounds like I'm getting some back pressure in the pipes but what do I know. I ordered the 45/155 setup so I guess I'll give that a try.
ivar
TT Racer
Can you elaborate a little more, is this on top end? Does it feel like it "hesitates" (=lean) or is it more blubbery/struggling?
My guess is that you'll run pig rich with those jets at that altitude.
BTW, which year is your bike? And is it 790 or 865cc?
(they've got different stock needles - the needle used in the 865 is richer in the midrange and allows a slightly smaller main jet )
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Gretsch
Rocker
I've noticed popping on deceleration (not a backfire exactly) and when I'm running at low speeds. Top end performance seems good but there hasn't been much improvement on the bottom end. I sometimes smell gas too so I would say rich too, but again I'm a FNG at this.
Bike is a 2006 with ~5500 miles on it. The engine is a 790.
Gretsch
Rocker
Cool thanks for the tip! So, would 45/155 make me run leaner? I'm confused. I would think that the larger number would indicate wider = more gas = richer. Unless it's like shotgun gauges and it works the other way around. Again sorry for the dumb questions.
BlueJ
Blue Haired Freak
Gretsch- You are correct, bigger numbers mean more fuel, means richer.
For your bottom end boost, the main jet won't do anything. You could try just the larger (45) pilot and leave the main at 140. 155 seems excessive, especially at altitude. You could also try shimming the needles - that will give you a noticable difference at low-mid range throttle settings. Now, as to whether that noticable difference is good or bad is another story!! But it's an easy experiment.
Good on ya for taking the plunge. Even if you cannot get it running "perfectly" there's a certain satisfaction to knowing you did it yourself.
Cheers!
For your bottom end boost, the main jet won't do anything. You could try just the larger (45) pilot and leave the main at 140. 155 seems excessive, especially at altitude. You could also try shimming the needles - that will give you a noticable difference at low-mid range throttle settings. Now, as to whether that noticable difference is good or bad is another story!! But it's an easy experiment.
Good on ya for taking the plunge. Even if you cannot get it running "perfectly" there's a certain satisfaction to knowing you did it yourself.
Cheers!
Iceseven
750cc
Gretsch, I am at 125 mains and 42 pilots that is with Scrambler tors, restrictor plate, stock filter and snorkel removed and hit it right on with jetting, the 42 pilots cured my popping on decel since my stocks were 40's. I am at around 7200' asl. I checked with the local dealer and he said that my setup was what they are typically using for Scramblers with tor's in the area.
Going too rich at altitude is not the best since there isn't enough oxygen to compensate so it just runs rich.
Gretsch, we gotta hook up some time and ride like you mentioned before but I spend my weekends climbing around Estes and just haven't been riding much. Maybe soon though,
Ice
Going too rich at altitude is not the best since there isn't enough oxygen to compensate so it just runs rich.
Gretsch, we gotta hook up some time and ride like you mentioned before but I spend my weekends climbing around Estes and just haven't been riding much. Maybe soon though,
Ice
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Kirkus51
Hooligan
I'm running TORs on an 07 Black. I believe that whatever the bike came with is what I'm running. I also "burble" on decelleration. I'm happy as a clam with what I got. My bike runs just fine in the beautiful Mile Hi city.:headbang2:
On a note, you got me to wondering, so I've got a call into Erico to see if they did any carb work on my bike when it was being repaired. Got a call back from Erico and I'm running whatever the factory puts in em. As I said it's running fine for my tastes.
I've been happy as a clam with Erico. They've gotten me in and out really fast and the guys were nice and very helpful. Jut goes to show you.
On a note, you got me to wondering, so I've got a call into Erico to see if they did any carb work on my bike when it was being repaired. Got a call back from Erico and I'm running whatever the factory puts in em. As I said it's running fine for my tastes.
I've been happy as a clam with Erico. They've gotten me in and out really fast and the guys were nice and very helpful. Jut goes to show you.
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Gretsch
Rocker
Thanks Kirk. Just a head's up about Erico. Ice and I have both had bad experiences with them. I've never used their service department but I feel MUCH better working with Kevin, Matt, and the other guys at Foothills.
Brent send me 135s and 140s to try but Pat's jetting caculator is showing 155s and 45s with one shim. I'll take a snapshot and show you what I'm talking about.
Ice - Hell yes lets do it.
Thanks Guys!
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sweatmachine
moped
I WOULD NOT run 45 pilots anywhere, especially at your elevation. You'll be fine with the stock 40s or 42s, either way you'll have to play with the idle mix screws.
DO NOT even bother with the 155 mains. You'll be puking gas out the exhaust pipe rich.
You might even need to go as small as 125 mains, certainly not above 135s.
DO NOT even bother with the 155 mains. You'll be puking gas out the exhaust pipe rich.
You might even need to go as small as 125 mains, certainly not above 135s.
Gretsch
Rocker
Thanks Sweat! So is the Jetting calculator messed up or did I fuck it up somehow?
sweatmachine
moped
the calculator is fucked.