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Carburetor help !

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I have my lock nut on my main jet holder screwed down about three twist. Could that cause low acceleration & poor bike speed ??

Edited by Chevyy2stroke

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:confused: What ?

 

Yep I was gunna answer this but read it and went WTF. Maybe he's talking about the throttle slide thinking the needle is the MJ? and the lock nut is the adjustment on the throttle cable.

 

Too low an idle could cause a bog?

 

 

Glad I'm not the only one....lol.

 

 

This

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I have my lock nut on my main jet holder screwed down about three twist. Could that cause low acceleration & poor bike speed ??

 

Would be glad to help, but not real clear about your question.  Try and ask it differently, or with more detail. 

 

I don't see the bike info either, but one of your other topics/posts, you were asking about a 95 cr80.  Is this the bike in question?

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Would be glad to help, but not real clear about your question.  Try and ask it differently, or with more detail. 

 

I don't see the bike info either, but one of your other topics/posts, you were asking about a 95 cr80.  Is this the bike in question?

 

X2.

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I have my lock nut on my main jet holder screwed down about three twist. Could that cause low acceleration & poor bike speed ??

Absolutely! Take it to 5 twist!
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Theres a lock nut on my main jet and Im curious on what the difference would be if I were to screw it toward the jet or away from it

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Do the cr80s have a removable nozzle like the 250s? If so screw it all the way in. Then screw the main jet all the way in. They should both be completely seated. Maybe I'm wrong but that's whatit sounds like to me.

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I'm assuming inside the carb you're talking about but there isn't a lock nut on anything in a carb. The only lock nut that's adjustable is the idle control screw on the outside . It pushes against the throttle slide forcing it up when screwed in increasing throttle speed and decreasing engine idle speed if it's screwed outwards. The brass screw to the right of that is your air metering screw that supplies more or less air to the pilot circuit. There aren't any stupid questions here and it sounds like you need help. There are a lot of people willing to help you but you need to be specific as possible or take a picture of what you are looking at so we know. Tuning a carb. in a text message can't be done but we can get you close if you are serious about fixing your problem. If you don't know take a pic and say wth is this ? That's why this forum is here , to help . 

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Theres a lock nut on my main jet and Im curious on what the difference would be if I were to screw it toward the jet or away from it

Re reading your post , Keith72 probably answered your question thats a lock nut on a removable nozzle and both should be tightened all the way in . 17 and 28 snug to the carb body , not superhuman tight . That nut would back out against the jet i would think , Anyone ? 

Capture.PNG

Edited by Beau 88

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In the carb next to my pilot !Thats like as clear as it gets ...

Whoa there fella...lol. The reason it DOES get "more clear than that", is because the people who are asking have a very good idea of what's going on inside a carburetor and what you have said makes no sense in terms of what we know about carbs. So it's not that we're trying to be tools (well ya maybe we're tools ;) ) we just need YOU to be more clear so that we can help you.

I'm going to try to help you here by making this very easy for you. Assuming your bike's a 1995 cr-80, here's a diagram of your carburetor. You tell us which # the part is on the diagram it is that you are adjusting:

Cr-80_carb_1995_zpse8e639c7.jpg

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Re reading your post , Keith72 probably answered your question thats a lock nut on a removable nozzle and both should be tightened all the way in . 17 and 28 snug to the carb body , not superhuman tight . That nut would back out against the jet i would think , Anyone ?

Ah crap.....you beat me...lol.

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This is the problem im having, (not the ticking). I figured since I just rebuilt the whole top end, the only other thing that could be causing the problem is the carb & that's when I came for help. Buttt ! This video should give you guys a good understanding of what the situation is ....

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This is the problem im having, (not the ticking). I figured since I just rebuilt the whole top end, the only other thing that could be causing the problem is the carb & that's when I came for help. Buttt ! This video should give you guys a good understanding of what the situation is ....

 

 

Ok.  So give us some history on the bike.  You said you rebuilt it.  What else, if anything did you do or change?  Before you did the rebuild was the bike running properly?  Are the outside conditions significantly different now from when the bike last ran well?  Did you install OEM or aftermarket piston?  Did you install an "A" or "B" piston and did you check end gap clearance when you installed the new piston?

 

Also, I notice in the video there is a LOT of spooge on the right side of the swingarm which would have leaked from the joint where your silencer joins the pipe...  Can't see where the antifreeze is coming from...do you just need to tighten that hose clamp a tad, or is it dripping down from the head due to improperly installed gasket or o-rings?  Did you torque the base and head nuts to spec and use crisscross method?  Oh, and there is an intake and exhaust side to the piston....is it properly configured in the cylinder?

 

Because here's what I think.  The bike is either jetted WAY too rich, or something mechanical (such as bad compression or if your head gasket or o-rings aren't sealing) is mimicking rich jetting.  Is it possible the previous piston may have been a "B" and that the bore diameter is worn larger than spec....then you maybe installed the slightly smaller diameter "A" piston?  This could result in too large of end gap spec and result in low compression even with a new top end.

 

Have you checked the compression? 

Edited by Fattonz

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