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2002 honda xr80r main jet help

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I have a 2002 xr80r that I bought. I cleaned the carb in a soak and bought a carb kit. After putting it all back together it starts great and idles great but has a terrible mid range bog once it is warmed up. Removing the air box made no difference. Moving the needle clip up just made it run lean and worse. Float level is correct. The kit I bought did not have numbers on the jets so I'm thinking my main might be too big. If I put the the choke at 1\2 it runs great and idles great. No bog at all. So am I on the right track or did I miss something? Will moving the needle up even more be worth trying? I feel like I'm already rich and moving the needle up would just make that worse, correct? Thank you in advance for any help you can provide. 

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Moving the clip Downm (away from the top/flat) will richen things but only a tiny bit. No offense but you bought a crappy no-name kit. You should of spent the money on OEM jets. If you still have the original needle, try it, then try the original main jet.

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No offense taken. I am using the stock needle. I'll put the stock main jet back in and see how things go. 

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38 minutes ago, jeopardy98 said:

No offense taken. I am using the stock needle. I'll put the stock main jet back in and see how things go. 

http://jetsrus.com/

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11 hours ago, jeopardy98 said:

No offense taken. I am using the stock needle. I'll put the stock main jet back in and see how things go. 

Start with the clip on position #3

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Stock airbox and exahust with the stock jetting works the best.

If you have an opened up pipe and airbox, using the FMF jetting specs works well.

Do not use a 'pod' air filter unless you really love playing with the jetting.....

No matter what jetting you use, it will always be sluggish and slightly unresponsive with the stock carb.

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4 hours ago, William1 said:

Start with the clip on position #3

That's where I am. Hopefully the main is just too big. 

3 hours ago, Krannie McKranface said:

Stock airbox and exahust with the stock jetting works the best.

If you have an opened up pipe and airbox, using the FMF jetting specs works well.

Do not use a 'pod' air filter unless you really love playing with the jetting.....

No matter what jetting you use, it will always be sluggish and slightly unresponsive with the stock carb.

Stock everything. I really hope a stock main is what I need. 

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Okay stock main jet and pilot jet and new stock air filter. Bike idles even worse now. It surges and has a hanging idle. Once it dies it will not start back up and just backfires. Plug is gas soaked. I'm at a loss. 

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Ignore the main jet for now, it only comes in to play close to and at WOT.

You have a new, OEM pilot, good. Where did you set the fuel screw? All the parts on it and all in good shape?

Float height checked? Float needle seat and needle sealing?

Once the engine is hot, you should not use the choke. If you did, you may of flodded it. Kick a bunch with the plug out, let it sit a little while, confirm you still have a strong blue spark and put the plug back in. No choke, try to start it.

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28 minutes ago, William1 said:

Ignore the main jet for now, it only comes in to play close to and at WOT.

You have a new, OEM pilot, good. Where did you set the fuel screw? All the parts on it and all in good shape?

Float height checked? Float needle seat and needle sealing?

Once the engine is hot, you should not use the choke. If you did, you may of flodded it. Kick a bunch with the plug out, let it sit a little while, confirm you still have a strong blue spark and put the plug back in. No choke, try to start it.

I did remove the plug and clear the cylinder. It did start but died back out quickly. Float height is the only thing I haven't checked. I was thinking if it was too high it would be leaking out the overflow hose. 

Would incorrect float height cause issues such as mine? I noticed if I turn off the petcock the idle shoots up and it dies pretty quickly. 

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27 minutes ago, jeopardy98 said:

I did remove the plug and clear the cylinder. It did start but died back out quickly. Float height is the only thing I haven't checked. I was thinking if it was too high it would be leaking out the overflow hose. 

Would incorrect float height cause issues such as mine? I noticed if I turn off the petcock the idle shoots up and it dies pretty quickly. 

Too high a float will make the bike run rich. Do not just move it but set it EXACTLY as your manual instructs.

Normally, once the fuel level in the bowl drops, the idle will 'race' then stall.

Fuel level would have to be super high to leak out the drain hoses. In some cases, instead of coming out the vent hoses, it simply runs into the cylinder. You can sniff the oil to see if it smells like gas. If it does, you'll need to change the oil.

Everything must be correct for it to run right. Did you check the fuel screw setting? It should be appx. 1.75 turns from gently closed. The fuel screw is a fine adjustment to the pilot jetting circuit.

 

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2 hours ago, William1 said:

Too high a float will make the bike run rich. Do not just move it but set it EXACTLY as your manual instructs.

Normally, once the fuel level in the bowl drops, the idle will 'race' then stall.

Fuel level would have to be super high to leak out the drain hoses. In some cases, instead of coming out the vent hoses, it simply runs into the cylinder. You can sniff the oil to see if it smells like gas. If it does, you'll need to change the oil.

Everything must be correct for it to run right. Did you check the fuel screw setting? It should be appx. 1.75 turns from gently closed. The fuel screw is a fine adjustment to the pilot jetting circuit.

 

Manual calls for 2 1\8 on the air screw. I set it at 2. I originally thought I was running rich so I guess I'll check the float level and set it per the manual. Thanks for the replies. I'll report back either way. 

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You are close enough on the screw. !/4 turn either direction is typical fine adjustment depending on air density.

Take your time and be 100% confident you have things right.:thumbsup:

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4 hours ago, jeopardy98 said:

I did remove the plug and clear the cylinder. It did start but died back out quickly. Float height is the only thing I haven't checked. I was thinking if it was too high it would be leaking out the overflow hose. 

Would incorrect float height cause issues such as mine? I noticed if I turn off the petcock the idle shoots up and it dies pretty quickly. 

Did you buy new jets or did you re-use what was previously installed(for the stock ones)? I would buy new stock ones if I were you. I have a 1999 xr100r and the stock jetting in a brand new carb was lean and caused a surging idle. I replaced stock with a larger pilot and main and things were way better. But I agree with the comments above start at ground zero with new stock. I have spent more hours messing with this stuff on small bikes than on all my other larger bikes combined and it can be grief with too many variables and unknowns set it all back to stock and work from there. 

Did you carefully check the tank? There is a mesh filter inside(at least on the 100) that can get clogged and can cause inconsistent fuel flow and weird problems. You say it started and then died out quickly was this with the choke on or off? These bikes are notorious for idle issues but if I were you I would go back and carefully go over all my work and also make sure all seals are clean and tight. The fuel system on these bikes is finicky so take your time and make sure things are super clean as you go back over it.

Edited by Chaconne

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I have a 2002 xr80r that I bought. I cleaned the carb in a soak and bought a carb kit. After putting it all back together it starts great and idles great but has a terrible mid range bog once it is warmed up. Removing the air box made no difference. Moving the needle clip up just made it run lean and worse. Float level is correct. The kit I bought did not have numbers on the jets so I'm thinking my main might be too big. If I put the the choke at 1\2 it runs great and idles great. No bog at all. So am I on the right track or did I miss something? Will moving the needle up even more be worth trying? I feel like I'm already rich and moving the needle up would just make that worse, correct? Thank you in advance for any help you can provide. 

At this point you were lean (as indicated by improvement by adding half choke) raising the clip leaned it even more.

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14 hours ago, Chaconne said:

Did you buy new jets or did you re-use what was previously installed(for the stock ones)? I would buy new stock ones if I were you. I have a 1999 xr100r and the stock jetting in a brand new carb was lean and caused a surging idle. I replaced stock with a larger pilot and main and things were way better. But I agree with the comments above start at ground zero with new stock. I have spent more hours messing with this stuff on small bikes than on all my other larger bikes combined and it can be grief with too many variables and unknowns set it all back to stock and work from there. 

Did you carefully check the tank? There is a mesh filter inside(at least on the 100) that can get clogged and can cause inconsistent fuel flow and weird problems. You say it started and then died out quickly was this with the choke on or off? These bikes are notorious for idle issues but if I were you I would go back and carefully go over all my work and also make sure all seals are clean and tight. The fuel system on these bikes is finicky so take your time and make sure things are super clean as you go back over it.

Tank is plastic and was cleaned thoroughly. I also bought a new petcock. 

New stock jets and needle. I'll check float height and double check everything else. Thanks!

11 minutes ago, Red800rider said:


At this point you were lean (as indicated by improvement by adding half choke) raising the clip leaned it even more.

Thanks, I hope it is just a float that is set incorrectly. 

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It's been a bit since I could get back and update: I took the carb off and adjusted the float to 22mm exactly. It was off by several millimeters. I reinstalled the carb and it fired right up. I got it nice and warmed up and adjusted the idle as well as the air screw. It was running good and I took it for a rip. No bog, good response through the revs so I thought it was great. Put it away and the next day it would not start at all. With choke, without, nothing worked. I pulled the plug and it was black and gas soaked. I got 2 new plugs. When I put the new plug in it fired first kick with the choke on but now when I turn the choke off it revs much higher than it does with the choke off. I can't get it dialed in now. I got it running okay and took it out and ran it down the road and did a plug chop and this is what the plug looks like.


Any ideas as to what to try next?

Screenshot_2017-07-24-20-54-59.png

Screenshot_2017-07-24-20-54-56.png

Screenshot_2017-07-24-20-54-53.png

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On 07/24/2017 at 11:02 PM, THE KRAN said:

You still have debris in the carb, or from a rotting fuel line getting into the carb.

Ignore what the plug looks like, it is meaningless

 

On 07/24/2017 at 11:02 PM, THE KRAN said:

 

Okay I'll check it again but I have all new jets and a new petcock and new fuel hose. Also a new float.

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Okay I opened it up again. Cleaned everything, blew it all out, and out in all new oem jets. Double checked the float height with float gauge. Exactly 21.5mm. I put it all back together and it is doing the exact same thing. It wil start and idle fine but  as  soon as I touch the throttle it revs sky high and hangs a few seconds before returning to idle. I checked for air leaks with wd40 and verified the throttle slide isn't sticking.

I'm completely stumped. 

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