misteright1_99
Member
I reshaped the intake and exhaust gaskets and the intake and muffler to match the port on the engine. My exhaust was covered/ blocked by at least 20%. Dramatic improvement for a few hours grinding....
I reshaped the intake and exhaust gaskets and the intake and muffler to match the port on the engine. My exhaust was covered/ blocked by at least 20%. Dramatic improvement for a few hours grinding....
Marktur
Member
I"m having the same exact problem as described - seems to bog at full throttle. I'm set at the last notch to the top - leanest setting. My idle is also slow with the idle screw turned all the way in if that's any hint as well.
I reshaped the exhaust gasket and manifold to match the motor. I guess I'll do the intake as well. I'm thinking it needs more air at WOT...reason I think that is because I didn't have this problem until I put the o-ring in the carb to prevent air leaks...
At 3/4 it will get up to 27-28 after a long pull, but then I open it up all the way, and it sounds boggy and I drop a couple of mph. I did not notice this before I went from 44t to 40t, because I didn't let the motor wind out. Now I can run full throttle all day long, but I'm not going any faster.
I will try running it without the airfilter on when it stops raining.
I reshaped the exhaust gasket and manifold to match the motor. I guess I'll do the intake as well. I'm thinking it needs more air at WOT...reason I think that is because I didn't have this problem until I put the o-ring in the carb to prevent air leaks...
At 3/4 it will get up to 27-28 after a long pull, but then I open it up all the way, and it sounds boggy and I drop a couple of mph. I did not notice this before I went from 44t to 40t, because I didn't let the motor wind out. Now I can run full throttle all day long, but I'm not going any faster.
I will try running it without the airfilter on when it stops raining.
fastboy9
Member
Ok the problems back again 
. I recently fixed my air leak on my carb so I think it might now not be getting enough air. Also Is it possible to bore out the carb jet? However it sounds like bogging from too much fuel, so maybe it does need a higher flow air filter.
. I recently fixed my air leak on my carb so I think it might now not be getting enough air. Also Is it possible to bore out the carb jet? However it sounds like bogging from too much fuel, so maybe it does need a higher flow air filter.
B
BSA
Guest
I think that the carb is fundamentally carp, such a pain to take the hole thing apart just to change the mixture is such a pain. You could tray a K&N type filter, might be a bit pricey though.
BSA
BSA
fastboy9
Member
I've got a few K & N air filter's around from other bikes and things but they are way too big. My air filter is a custom job so I've drilled a few more holes into it and I'm going to see how this goes. Will probably ride over to the girlfriends tommorow so should get a good chance to see how the engine runs now.
Fastboy
Fastboy
Marktur
Member
Fastboy - show us your air filter...
Did the extra air holes fix the problem? If it did, I'll invest in the $35 K&N filter...
Did the extra air holes fix the problem? If it did, I'll invest in the $35 K&N filter...
fastboy9
Member
Heres a pic that kinda shows it. its basically the same as these ones: http://www.motoredbikes.com/showthread.php?t=4314&highlight=air-cleaner&page=2
It didnt make a difference at all really, however the engine did seem to rev higher before it bogged down. I'm really stuck for ideas now
. I've got to sell this bike soon and I cant really sell it with it acting like this.If you want to get a K&N filter, the model number is RC-2550. Ghost has got one fitted too his bike, but not sure about the clearance to most frames seat tube.
Fastboy
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sparky
Active Member
I was going to suggest it was an air leak.Ok the problems back again
If you fixed the air leak after tweaking with the air:fuel mixture... I'd tweak the mixture again. It'll make a difference for sure.
I couldn't imagine how a K&N filter is gonna not make it bog down, tho. It is most definitely a carby problem... most problems usually come from the carb. I think the carbs with hi & lo jets work best for our application of fine tuning for torque & speed.
fastboy9
Member
I thik the jet isnt large enough. Next time I get a chance I'm going to try boring that out. Not sure how but I'm sure I'll find out.
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fastboy9
Member
I have had a breakthrough on my bike, before it was running awfully but I didnt know any different. It use to bog out at full throttle high speed, you know, that same old situation of it hitting about 25 then slowing down to 23 then back up again. Well I took the float bowl off of the carb and found that the jet wasnt screwed in! it was just barely in the threaded hole.
I took the jet out to make the hole bigger, I think it was this that fixed the problem.
This is how you do it:
To make it even easier for you, loosen the clamp on the carb, where it attaches to the intake manifold tube. And see if you can just turn the carb to the side, just more simple that way so you dont have to disconnect the throttle and everything. Next make sure the fuel tap is turned off, and that you have laid some newspaper on the floor under the bike as petrol is likely to spill out. Now unscrew the two screws that hold the bowl on to the bottom of the carb; there will be a lot of petrol in there, so you might as well pour it back into the tank carefully. Do not lose the white float!! From here you will now see a little brass component, this is the jet.
1. First unscrew the jet from the carb, (the jet is a brass part of the carb with a little hexagonal part on it that allows you to unscrew it)
2. Now find the end with the tiny little hole in it. This is what sucks the fuel up out of the bowl. At high speed the engine is trying to suck loads of fuel up, but the hole is too small to supply the high demand, so the mixture leans out, potentially damaging your engine.
3. So get a drill bit or something to widen the hole, I used the point on a flat drill bit, you know the ones, not a twist one but a flat plate with a sharp edge. It is extremely important to only widen it by the most tiny tiny tiniest litlle bit, too much and you will have negative effects. (It is possible to make the hole smaller again but it takes a long time. Heres a thread that tells you how to do it: http://www.motoredbikes.com/showthread.php?t=5988). The brass is very soft, so take it easy, as more will file away than you think. It is best to widen it by a tiny bit and then test, and keep repeating until the bike is running just how you want it.
4. Now blow through the jet as hard as you can to get rid of any muck that might have got into it.
5. Next screw the jet back in to the carb, do not over tighten it as the brass thread will collapse with the most minimal of force.
6. Now re assemble the carb and take it out for a test ride. If you get the same result as me, then you won't stop riding until you run out of fuel, the difference is amazing!
I'm going to post this in a few threads because a lot of people having this problem and I'm pretty sure this is the solution.
Have fun!
Fastboy
I took the jet out to make the hole bigger, I think it was this that fixed the problem.
This is how you do it:
To make it even easier for you, loosen the clamp on the carb, where it attaches to the intake manifold tube. And see if you can just turn the carb to the side, just more simple that way so you dont have to disconnect the throttle and everything. Next make sure the fuel tap is turned off, and that you have laid some newspaper on the floor under the bike as petrol is likely to spill out. Now unscrew the two screws that hold the bowl on to the bottom of the carb; there will be a lot of petrol in there, so you might as well pour it back into the tank carefully. Do not lose the white float!! From here you will now see a little brass component, this is the jet.
1. First unscrew the jet from the carb, (the jet is a brass part of the carb with a little hexagonal part on it that allows you to unscrew it)
2. Now find the end with the tiny little hole in it. This is what sucks the fuel up out of the bowl. At high speed the engine is trying to suck loads of fuel up, but the hole is too small to supply the high demand, so the mixture leans out, potentially damaging your engine.
3. So get a drill bit or something to widen the hole, I used the point on a flat drill bit, you know the ones, not a twist one but a flat plate with a sharp edge. It is extremely important to only widen it by the most tiny tiny tiniest litlle bit, too much and you will have negative effects. (It is possible to make the hole smaller again but it takes a long time. Heres a thread that tells you how to do it: http://www.motoredbikes.com/showthread.php?t=5988). The brass is very soft, so take it easy, as more will file away than you think. It is best to widen it by a tiny bit and then test, and keep repeating until the bike is running just how you want it.
4. Now blow through the jet as hard as you can to get rid of any muck that might have got into it.
5. Next screw the jet back in to the carb, do not over tighten it as the brass thread will collapse with the most minimal of force.
6. Now re assemble the carb and take it out for a test ride. If you get the same result as me, then you won't stop riding until you run out of fuel, the difference is amazing!
I'm going to post this in a few threads because a lot of people having this problem and I'm pretty sure this is the solution.
Have fun!
Fastboy
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