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Discussion Starter · #1 ·
Well, after a long drawn out reassembly and assembly (just for jetting and some suspension work LOL), my rappy is now running again.

I have two initial questions:

I set my valves to .004 and .006, which is within factory spec, but on the tight end of spec. I did that because I'm used to working on turbodiesels and I always set the valves tight. Is that ok or should I go back in and set them to .006 and .008? Keep in mind my quad is mostly stock with only about 10 hrs of use.

Also, the bike smokes a bit at idle, and when I rev it (I haven't gotten out and taken it through the gears yet) it hangs a little before it comes back down to idle speed and smokes more. Does this mean my mixture screw needs to be adjusted?
 

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generally when they don't return to idle quickly, the pilot circuit is lean.

you can run the valves at those clearances but you'll have to check the intakes more often, the intake valves are a soft material so they get eaten away by the valve seats and receed into the head, that is why they are always tight when you go to adjust them.
 

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CoalShedRacing said:
the intake valves are a soft material so they get eaten away by the valve seats and receed into the head, that is why they are always tight when you go to adjust them.
Would Ferria valves be included in theis or just the stock?
 

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I've been running them for a while now but I don't have a whole lot of hours on the motor. They do tighten up, but it seems that they don't tighten up nearly as quick or as bad as the stockers.
 

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Discussion Starter · #5 ·
CoalShedRacing said:
generally when they don't return to idle quickly, the pilot circuit is lean.

you can run the valves at those clearances but you'll have to check the intakes more often, the intake valves are a soft material so they get eaten away by the valve seats and receed into the head, that is why they are always tight when you go to adjust them.
Then I wonder why the smoke? I'm running 25 pilots at 1k ft elevation. My only mods are port matched intake boots, no lid, cleartube tuned, and no sparky. I think it was like 50* in my garage.
 

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Discussion Starter · #7 ·
All I did besides the suspension work was jet, do the cleartube method of tuning and the float mod, and took the lid off w/ K&N.
 

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firstraptor said:
CoalShedRacing said:
the intake valves are a soft material so they get eaten away by the valve seats and receed into the head, that is why they are always tight when you go to adjust them.
Would Ferria valves be included in theis or just the stock?
The Ferrea valves do "seat in" during the first 10 hours but after that they pretty much stay where they are.
I adjusted mine after the first 10 hours and they did tighten up a little bit but probably 50 hours later and they are still within specs.
 

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Discussion Starter · #9 ·
Any other suggestions about the hanging revs and smoke?

CSR: as for the pilot circuit being lean, I'm running 25 pilots which already seems big to me considering what people have listed in the "jetting that works" thread. People with full exhausts are running 25 pilots and all I have is the float mod, cleartube tuned, ported intake boots, and K&N with no lid.
 

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you need the 25 pilots.

any mod that increases power also raises cylinder pressures.....more air with more fuel in the same space = elevated cylinder pressures. This might be a stretch but its possible your rings were worn originally and the increased cylinder pressures from removing the airbox lid amplified the problem.

you could perform a leak down test on the rings to be sure.
 

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I'd hope not too but its very difficult to diagnose a "smoking" problem over the internet.....do the leakdown test and let us know the results, that will at least eliminate one thing.
 
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