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xr650l not running after de-snorkle & de-smog

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I have a new 2006 xr650l, and on Monday I completed the de-snorkle mod and the de-smog mod with the IMS covers. I also added a brand new UNI filter to the bike. I then changed the oil and oil filter, clean the oil filter screen, and then I have not run the bike since I did the mods, nor did I test drive it after the mods. So today was my first chance to ride it.

Anyway, it was really hard to start today around 12 noon, and it is nice and sunny out and about 70 degrees. I had to use full choke, and it finally started, but once I tried to hit the throttle, the bike keeps stumbling and trying to shut off. So what did I do to the bike with these simple mods as described above? I have a big ride tomorrow and I need the bike running. Please let me know ASAP. Thanks.

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Now that you have opened things up to let it get more air you need to rejet to add more fuel.

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I am wondering if I messed up the carb vent hoses, and if that is the problem. Either it is not getting enough fuel, or I am starving it of air somehow, or there is a vacuum issue at the carb now. I followed Dave's mod page for the de-smog, but he says that it might differ since his bike is an older 95 and mine is a 2006, so I wonder if there is a vacuum hose issue that i did wrong?

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if you did change jetting and pulled the carb, re-check your choke adjustment, 1-2mm thread to exposed tip when lever is towards the bars or "off"

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Nope, jetting is stock, and there is a Supertrapp exhaust on it as well.

I just removed the seat and the Uni air filter and started it back up to see what it is doing. It certainly is not the air filters fault, it seems to be dying at the carb for sure. The second I touch the throttle, the bike dies now. My guess is it is the fuel issue and way to lean right now for the mods on the bike. What do you think?

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Nope, jetting is stock, and there is a Supertrapp exhaust on it as well.

I just removed the seat and the Uni air filter and started it back up to see what it is doing. It certainly is not the air filters fault, it seems to be dying at the carb for sure. The second I touch the throttle, the bike dies now. My guess is it is the fuel issue and way to lean right now for the mods on the bike. What do you think?

with the de-snorkle, de-smog, uni filter and supertrapp exhaust you definatley need to re-jet the carb. These bikes comes way lean from the factory.

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I just called my local Honda dealer, and they carry the 55, 155, 160 jets in stock. He said they are plastic Keihn jets, instead of the metal type jets. Does this matter what material jets I would use? Also, he says that they don't have the slow jets in stock. So now i am confused about the jetting then, b/c what is a 55 jet considered and what is a 160 jet considered? Are they both fast jets?

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Just remember that opening up the air box is allowing more air to enter the engine and opening up the exhaust is allowing more air to exit the engine. Less restriction lets your engine breathe more effectively.

More air in, more air out.

Now you need to increase fuel availability to match the better breathing. If you didn't change the fuel volume to match the increased air volume, your bike is going to run lean.

When I uncorked my 600R, I went from a 125 main jet to a 170, and from a 52 (55?) pilot jet to a 68. I think I finally settled on 2-1/2 turns out on the fuel screw. A critical step is to make sure that the float height doesn't get disturbed. Make sure it's right (check your manual). These were settings for my 600R with a full Yosh' system, your 650L may be different.

Good luck.

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The numbers on jets refer to their size. However, I don't think there's any uniformity amongst the different carb makers. Keihin uses a different numbering system than Mikuni, and aftermarket companies like Factory and Dynojet use propietary numbers also for their jet sizes.

Just remember that the higher the jet number, the larger the diameter of the orifice in the jet. A 152 main jet has a smaller fuel passage than a 165 main jet. A 52 pilot jet has a smaller fuel passage than a 65 pilot jet, etc..

You will also have to adjust your fuel screw. The fuel screw meters the amount of fuel being delivered to the engine via a bypass orifice on the engine side of the carbs venturi (throat). By turning the fuel screw out from seated, the orifice is less restricted and allows more fuel to flow and richens the mixture at idle and small throttle openings.

Do not use much torque when you seat the fuel screw. It's possible to damage both the carb and needle tip by tightening the air screw too hard to seat. Just let it gently bottom out, then count the number of turns out.

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in all seriousness.....When I changed a bunch of schtuff on my R model, I had to reset the air screw. Look in the manual and find out the standard setting and adjustment procedure.

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This is stock bike and the carb has never been meessed with. I understand that the larger the number the larger amount of fuel per jet, etc.

Ok, I just dove into this beeoch. I just removed the carb, and I pulled the two jets out, one says 50s which is a longer of the two jets, the other jet says 152. I assume these are the ones I am supposed to swap out for a 55 and a 158 or 160, correct? Since I have the whole thing apart, I guess I might as well complete the Dave mods on the carb.

Is it ok to use the plastic jets instead of the metal ones? Also, the screws that hold the carb plates on the carb are such junk. i was careful with them, and they still stripped out. Time to get some nice Allen/hex head bolts.

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This is stock bike and the carb has never been meessed with. I understand that the larger the number the larger amount of fuel per jet, etc.

Ok, I just dove into this beeoch. I just removed the carb, and I pulled the two jets out, one says 50s which is a longer of the two jets, the other jet says 152. I assume these are the ones I am supposed to swap out for a 55 and a 158 or 160, correct? Since I have the whole thing apart, I guess I might as well complete the Dave mods on the carb.

Is it ok to use the plastic jets instead of the metal ones? Also, the screws that hold the carb plates on the carb are such junk. i was careful with them, and they still stripped out. Time to get some nice Allen/hex head bolts.

Yes on the Dave's mods, I'm not sure about the plastic jets, I personally wouldn't run plastic jets. I got my jets for Dave's mods from here http://www.jetsrus.com/main_page.htm

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..........

Is it ok to use the plastic jets instead of the metal ones?

I've never encountered plastic jets.

I'm sure they'll work, but I'd rather switch 'em out in the near future with brass ones.

Just remember, it's not a moving part. It just gets screwed into the carb body and allows fuel to flow through it. Being in the float bowl, you know it's in a protected environment, so it's not like it's subject to damage.

If plastic is all that's available and you risk missing out on a ride you've been looking forward to, run 'em, then replace them later. They're only a few bucks each, right?

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Screw the plastic ones for now. They only had the fast jets (i.e. 160), but they had no Slow jets (i.e. 55) So, I just went ahead and ordered a 55 slow and a 160 fast in brass, but they won't get in until next Thursday or Friday. So, so much for riding during Memorial weekend.

Total for 2 jets from the Honda Dealer was $16.74 for Keihn jets to fit my stock Keihn Carb.

I went to Lowes and bought hex screws for the carb to replace the junk stock phillips screws. Go buy 2 packs of M4 .70 x 10 (total 4 screws) and 2 packs of the M4 .70 x 12 (total 4 screws). Plus I got a ten pack of the M4 split lock washers. So now I will concentrate on completing Dave's mods while I wait on getting the jets into my local dealer. Thanks for your help guys.

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Just an FYI....

The pilot jet is called a "slow" jet because that circuit meters fuel from idle to about 1/4 throttle opening.

Your slide cutaway plays a role in metering air to just past 1/4 throttle.

From just past 1/4 throttle to about 3/4 throttle your jet needle/needle jet combo handles the mixing chore.

From 3/4 throttle to WFO is where the main jet does it's job.

Someone please correct me if I'm wrong, this is the rule I've always followed.

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Screw the plastic ones for now. They only had the fast jets (i.e. 160), but they had no Slow jets (i.e. 55) So, I just went ahead and ordered a 55 slow and a 160 fast in brass, but they won't get in until next Thursday or Friday. So, so much for riding during Memorial weekend.

Total for 2 jets from the Honda Dealer was $16.74 for Keihn jets to fit my stock Keihn Carb.

I went to Lowes and bought hex screws for the carb to replace the junk stock phillips screws. Go buy 2 packs of M4 .70 x 10 (total 4 screws) and 2 packs of the M4 .70 x 12 (total 4 screws). Plus I got a ten pack of the M4 split lock washers. So now I will concentrate on completing Dave's mods while I wait on getting the jets into my local dealer. Thanks for your help guys.

I wish you hadn't already ordered the slow jet. I've got a brand new 55 here that I'm not using. It's too much for my bike, but then I have the stock exhaust. I'd have been more than happy to mail it to you. Either way, it sounds like you're back on track. You were running much too lean with your current set-up.

-Joe

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If you can still add to your order you may want to add a 158 in case the 160 is to much. It will be a differnt machine once you get it dialed in.:thumbsup:

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Thanks guys. Maybe I should have them order a 157.5 is what they could get, not a true 158. But my guess is that the bike will be running so good at the 160, that I won't care about trying the 158. :thumbsup:

I just finished drilling the slide, and grinding down the fuel screw, and reinserted that into the carb. Now I have to find a small ass washer for the slide needle. Then I just have to wait on the jets now, and I should be good to go. Heck, while I am at it, perhaps I should order a larger tank and get that in at the same time as the jets, and heck, maybe go ahead and order a E2 exhaust from White Brothers after I remove this Supertrapp exhaust. :ride:

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