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DR EVO
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1,757 Posts
Discussion Starter #1
hi....... i was wonder what everyone is running for jetting in their bikes. i have 185 main and 42 slojet(stock) the bike runs really well now, but the plug indicates possibly lean. there is an every so slight popping comin out the exhaust on deceleration, hardly noticeable though. i have a k+n, bigshot longs, and thunderslide kit in it. the kit calls for the 185 for these mods, then up to a 195 possibly for cam, head work and so on. is there a way to richen it up alittle without goin to the 195? the enrichener screw is 3 turns out. the bike runs 500% better than stock.
 

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Premium Member
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1,552 Posts
Hey otterbob,

Go one step up to a 190 main and 45 slow. This should cure the lean decelleration pop and aid in performance.
 

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DR EVO
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1,757 Posts
Discussion Starter #3
i next size i have is a 195. would that be ok? i will have to get a .45 from the dealer. they supposedly ordered one per my request so i will have to check.
 

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Premium Member
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1,552 Posts
Re: Jetting...

Hey Otter,

The 195 is a little fat for a primararily stock Evo. I'm running a 48 slow and 195 main along with a Thunderslide in the Keihin CV on a heavily modified 95" Twin Cam... SE heads, roller rocker arms, hi-comp forged pistons, SE 257 cams, 6200 RPM race ign., KuryAkyn Hypercharger and Samson 2 1/4" Street Sweepers with Torque Cones. This jetting is on the money for my mill! No flat spots, exhaust pops or carb farts. Smooth transition between circuits throughout the entire RPM range.

Your best bet is to pick up a 190 main and try that along with the 45 slow unless you like changing plugs real often. These jets may even be a little on the rich side for your 80 incher.

The popping may only be the result of a slight exhaust or vacuum leak. Try blocking off the exhaust exits with a wadded up rag and listen for leaks at the joints. Then spray WD 40 at the intake manifold to head and carb joints at an idle and listen for a raise in RPM. If it goes up, you've got an intake vacuum leak.

Hope this helps!

Later,
Mike
 

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DR EVO
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1,757 Posts
Discussion Starter #5
well i popped the 195 in er just to see how it ran and it ran good to top speed then it popped and farted around 75 and wouldnt go any faster. so i checked the plugs when i got home and the upper threads were jet black and sooty, along with the rim of the plug. but the white insulator was real white. hmm. does it take a while for a brand new plug insulator to darken up? so i put the 185 in it and it runs great. would i gain anything by changin the slow jet to a 45? also anyone with a heritage, what kind of top speed is normal for the heratige? without the windshield does it make a big diff?
 

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My bike is quicker without shield. Have been up to 110 but suspension doesn't like this speed. I run Stage one with vance and hines straight shots. Carb has 185 main and 48 slow. 48 slow made a big diff on carb cough and popping. It now never pops and only once in the while coughs if I don't warm up engine before I go.
 

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695 Posts
Sounds like riding the Autobahn. I've been on bikes going this fast but I don't think I'll try it on my Harley. Lot of wind out there at that speed isn't it? It's a lot of fun to ride that fast if your bike is built for it and the road is good.
 
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