New Mods...jetting...hard To Start

[jasonsb]

Just got back from Glamis...I spent the whole time playing with the jetting.

Here's what happened: It was the first ride since putting the stock carbs back on my mid ported motor. I took the bike up to Glamis with 340 mains, 27.5 pilots, needle in middle. The bike was VERY hard to start. I had to really increase the idle just to get it to start. I ran it as much as I could ...it kept stalling on me. The plugs were white(lean) but I didn't get a chance to run it WOT in 6th. So, I changed the jets to 350, same pilot(couldn't find parts), needle one notch rich. Now I could run it but it bogs nasty going up hills or steep dunes.

Can someone please help if they have experienced this?

[erbilabuc]

sounds like you are too rich, try going down on the mains and leaving the 27.5 in. After porting mine I started at 370 and worked my way down to 290 mains!

[Leadfoot350]

do a leak down test on it. 350 sounds big.

[BenBB]

Did the choke help at all or make it worse (flood it?)? I would guess you need to try the next size larger pilots, 30, and see if that helps. Also, where are the airscrews set now? Did you try adjusting them at all? The pilot jet controls mixture from zero to about 1/8 throttle, and the airscrews fine tune the mixture, so if it's hard to start AND you know compression is good, start there.

 

350 mains doesn't sound unlikely with the mods in your sig, although I dunno what air filter setup you've got...better to start rich on the mains and work your way down like erbilabuc said, but keep in mind the mains control mixture from about 3/4 throttle to WOT; if it bogs at WOT drop a size on the mains until it revs out clean.

 

So I would start by moving the needle clip back to where it was, 30 pilots, airscrews 1.5 turns out, and the 350 mains and see what happens. Good luck.

[jasonsb]

It did run better with the choke pulled out. The strange thing is that the plugs were white just from me running it hard a few times in 1st-3rd gear. It ran strong at WOT on the flats but fell on its face when I tried to race up a hill. It felt like I was going from 2nd to 4th gear. I haven't replaced the plugs so I can't tell you how the 350 jetting worked. Also, what about the needle position? SHould I put it in the middle or 1 notch lean? (stock cages with boyeson pro reeds, dual K&N filters) **air screws were 1 turn out

[jasonsb]

I took the carbs off last night and noticed that the throttle clip inside the slide was covering the hole...if it matters...just a thought since reading one of the forum yesterday that talked about covering the holes inside the slide.

[skykingcory]

350 is not unbelievable for your setup.

 

I currently run a 340 with fatties and my trail port. I'm also on the stock reed cages, just TDR reeds. Go up on your pilot if it is hard to start. I went from a 25 to a 32.5 on the pilot after porting. You will just have to do a plug chop on the mains to be sure though. I had trouble getting mine started also before I jumped up on the pilot. Starts 1st to 2nd kick now.

[Banchetta]

Agree, you might have to go up higher on the pilots....Larger pilots will help it start a lot better..make sure you didn't swap the carb bowls either...only one carb bowl is for the carb w/ the choke..

[spoin39]

Get some 27.5's and 30's and see how it responds. Pulling the choke out richens so you definately need bigger pilots. That doesn't explain the uphill bog (unless you were at idle) so I suggest moving needle up 1 notch.

[jasonsb]

Sometimes I get confused with "moving the needle up/down". Do you mean making the needle one notch leaner or richer? I have it one notch richer than the middle just because I couldn't get it to idle. I will try 30 pilots and then put the needle one notch leaner from the middle. I was told that it will run better because I have boyeson reeds.

What about a bog when climbing a hill 1/2 - full throttle?

[BenBB]

Yes try one clip leaner on the needle for the reeds=move clip up towards the blunt end; so second notch down from the blunt end of the needle. If it will start & idle (may need to adjust the airscrews and/or the idle speed to get a clean idle and off-idle response), and there's no bog or hesitation between about 1/4 and 3/4 throttle, I would do one circuit at a time: dial in the mains, then the pilot/airscrew, then the needle clip if necessary. The mains are the most important, you don't want to be lean there if at all possible (350's might be perfect, but it still may be lean). Good luck.

[Banchetta]

The needles only control 1/4-3/4 throttle....If you have a bog from 1/2-wot then the air/fuel mixture is different between the needles and mains....I'd leave the needle position for now, dial in the mains w/a wot run in 6th gear for 5-10 seconds and check the plugs...Dial in the pilots and air screws, then the needles....A richer pilot will affect the needles and mains since they are working all the time regardless of throttle position.....

[lincster]

I think you are lean on the mains and small on the pilots.

I run 370 mains, 30 pilots, Toomey needles on the 4th position from the top and have the same reeds as you. My bike runs awesome and all I do is ride at Glamis.

 

I have no porting either. I would try 390 mains and work down from there. Do the 30 pilots without even thinking about it.

Hope you didn't burn it up running it like you did.

Might want to do a compression check while you are at it.