Wont start now after taking carbs off

[clayton00grand]

OK after I started to notice a little bog down low almost like a stutter, I decided to pull it into the shop and take a peek at the carbs. I pulled the pipes off because I wanted to paint the exhaust portion it had looked kinda rusty on the outside. I popped the carbs out and then the reeds with the attached boost botttle off , look at the reeds noticed that the bottom of them just seemed further apart from the cage, so I tried flipped them around that seemed to tighten the clearance up. after cleaning the carbs which looked good by the way, but I figured I was this far might as well. I installed everything with new reed gasters and hooked everything back upa dn no dice, PLenty of good blue spark (awesome blue), gas in the bottom of the bowls, took plugs out and nothing on them and barely even noticed a smell on them. So I thought well maybe that reed flip messed me up so I took all back apart cleaned carbs again, and flipped back to originial position and still no luck and plugs still not damp at all. Everything looks good and this bike has always fired up at least within 5-6 kicks max, depending on temp outside.

List of mods include

Cool head with 19-20mm domes I think its been a while. Dual 28mm Mikuni carbs with 240 main jets, and pilot is too small I can't read it. Some sort of pipe no brand name, answer silencers, (bought ity with pipes) it was bored and .020 over and crank redone by tony ducas racing , granted I know its been a while since I have tore it down but It has never lacked on power. I put a +4 degree timing advance in it about 2 months ago and that helped a lot (key version) I'm at a cplete loss what to do next, The last time I rode it which was about week ago now, I can pull the wheels in 4th no prob. This whoel carp of everyone redoing there rings every so often is bull, unless you notice a huge power decrease its a waste. I haven't plus I still have 120 compression in both cylinders.

I just understand why gas isn't pulling into the cylinders. Someone please help me

[AKheathen]

OK after I started to notice a little bog down low almost like a stutter, I decided to pull it into the shop and take a peek at the carbs. I pulled the pipes off because I wanted to paint the exhaust portion it had looked kinda rusty on the outside. I popped the carbs out and then the reeds with the attached boost botttle off , look at the reeds noticed that the bottom of them just seemed further apart from the cage, so I tried flipped them around that seemed to tighten the clearance up. after cleaning the carbs which looked good by the way, but I figured I was this far might as well. I installed everything with new reed gasters and hooked everything back upa dn no dice, PLenty of good blue spark (awesome blue), gas in the bottom of the bowls, took plugs out and nothing on them and barely even noticed a smell on them. So I thought well maybe that reed flip messed me up so I took all back apart cleaned carbs again, and flipped back to originial position and still no luck and plugs still not damp at all. Everything looks good and this bike has always fired up at least within 5-6 kicks max, depending on temp outside.

List of mods include

Cool head with 19-20mm domes I think its been a while. Dual 28mm Mikuni carbs with 240 main jets, and pilot is too small I can't read it. Some sort of pipe no brand name, answer silencers, (bought ity with pipes) it was bored and .020 over and crank redone by tony ducas racing , granted I know its been a while since I have tore it down but It has never lacked on power. I put a +4 degree timing advance in it about 2 months ago and that helped a lot (key version) I'm at a cplete loss what to do next, The last time I rode it which was about week ago now, I can pull the wheels in 4th no prob. This whoel carp of everyone redoing there rings every so often is bull, unless you notice a huge power decrease its a waste. I haven't plus I still have 120 compression in both cylinders.

I just understand why gas isn't pulling into the cylinders. Someone please help me

did you leave your reeds dry when you put them back in? try just a little gas through the spark plug holes to get it fired up then use starting fluid to look for air leaks between the engine and carbs if it runs. if it dies, put your hand over the carb and feel the impulses. sounds like your reeds are worn and there's an air leak. btw what's the temp there?

[Screaming Yellow Zonker]

make sure the slides are not stuck open at all. If everything is good I would try some carb cleaner shot in the carbs to try and start. Starting fluid isnt that safe for 2 strokes.

[clayton00grand]

I debated trying that last night, what would make it not start now versus starting and and everything fine just before I pulled it into the shop. Since I have a timing advance key would it still have spark and maybe the key sheared off and its not telling things to get fuel at the right time? Would worn reeds cause it not to have much low end, thats the reason it was brought into the shop. I s say would come out of a corner a slow corner, and bog way down,almost die then pull clutch in get rpms up and let off clutch everything igood. The first night I got it back together and I got fed up with trying to kick it I thought what the heck I'll try to push start it by myself kinda hard but anyway, it ran for about 3 seconds just long enough for me to hear it barely I tried to jump on it so I could reach the gas better and could make it there in time. I don't have anyway to tell what mikunis I have, I have the brass lever push down choke., how do you measure for size of carb which side you measure I'm pretty sure its 28mm but not quite sure. NO choke tube present 2 totally different carbs from the stock ones.

 

make sure the slides are not stuck open at all. If everything is good I would try some carb cleaner shot in the carbs to try and start. Starting fluid isnt that safe for 2 strokes.

 

Slides are definately not stuck open either they slide very nicely.

[AKheathen]

I debated trying that last night, what would make it not start now versus starting and and everything fine just before I pulled it into the shop. Since I have a timing advance key would it still have spark and maybe the key sheared off and its not telling things to get fuel at the right time? Would worn reeds cause it not to have much low end, thats the reason it was brought into the shop. I s say would come out of a corner a slow corner, and bog way down,almost die then pull clutch in get rpms up and let off clutch everything igood. The first night I got it back together and I got fed up with trying to kick it I thought what the heck I'll try to push start it by myself kinda hard but anyway, it ran for about 3 seconds just long enough for me to hear it barely I tried to jump on it so I could reach the gas better and could make it there in time. I don't have anyway to tell what mikunis I have, I have the brass lever push down choke., how do you measure for size of carb which side you measure I'm pretty sure its 28mm but not quite sure. NO choke tube present 2 totally different carbs from the stock ones.

 

 

 

Slides are definately not stuck open either they slide very nicely.

if you don't have a t mic. you can trim a tooth pick so it barely fits against th slide, then measure the tooth pick. 25mm= 1 inch. try putting some 2 stroke oil on the reed where it seals against the cage and see if it starts.

[clayton00grand]

So you don't install the reeds dry? I cleaned them off the same time I cleaned the carbs.

 

 

 

if you don't have a t mic. you can trim a tooth pick so it barely fits against th slide, then measure the tooth pick. 25mm= 1 inch. try putting some 2 stroke oil on the reed where it seals against the cage and see if it starts.

[dajogejr]

I have never in all my years heard of oiling or "wetting" reeds upon installation.

The second the bike is kicked over to start it...the fuel/oil/air MUST go through the reeds to get to the cylinder.

Sounds like wiping before you poop...don't make sense....

 

A little gap is ok. More than a few thousands, flip the reeds over or replace them.

If petals are chipped or frayed...replace them.

[clayton00grand]

Thats what really ticks me off they were chipped or cracked or anything like that, all I did was take the carbs off clean them and pipes and paint them and toss new reed gaskets in reeds and now it won't start. I don't understand how it can go from running kinda crappy low end to not even starting. If the plugs aren't damp or anything like its not getting fuel, where would there should i replace the reeds u think Like I said before I pulled it into shop I could go kick it a few times start right up, and once warm and say I stalled it or shut off for a few minutes and fired back up one kick everyitime.

 

Is the main jet being 240 too small or anything, man right after I did the +4 degree timing key this thing ripped lots of low end and pulled wheels easy in 4th which it would not do before.

[fast500#12]

make sure your carb slides are in the right direction. ( cut out tward the rear ) timing has nothing to do with when the engine gets fuel, you have good sparks move on to the other two things needed for an engine to fire. AIR, FUEL.

[clayton00grand]

slides on these carbs wont go in wrong direction, Reeds are crackedor anything like that where and how would a air leak come about now.

[Screaming Yellow Zonker]

I would try setting the crank so one of the pistons is TDC and check your pickup on the outside of the fly wheel. If the little square lines up with pickup than the key isnt sheared.

[AKheathen]

I have never in all my years heard of oiling or "wetting" reeds upon installation.

The second the bike is kicked over to start it...the fuel/oil/air MUST go through the reeds to get to the cylinder.

Sounds like wiping before you poop...don't make sense....

 

A little gap is ok. More than a few thousands, flip the reeds over or replace them.

If petals are chipped or frayed...replace them.

it's called f'n troubleshooting- a bad habbit good mechanics develop :mad: a little bit of oil will temporarily make the reeds seal, and then you know there bad before you tear into them, since it started already and they got wet, you know to look elsewhere. have been doing this on sleds for years with a squirt bottle. the next step is to pour a capfull (a little more on small caps) of 2 stroke oil through the spark plug hole and barr it over slowly a couple of times to coat the pistons. if it starts after that, then you know there is a prblem there, cus not everyone has a compression gauge in their pocket.

[Snopczynski]

Right off the bat I cant tell what the hell is going on here now. However by jetting numbers in the first post it doesn't seem right on a set of mikuni 28mm carbs. I run a ported 350 with pods and exhaust at a 380 main jet with 28mm tm's. Elevation and parts on the bike are going to effect this though.

 

This sounds like it started off as a jetting problem, but may have evolved into something else. Best way to check the flywheel key without removing the flywheel, is to pull the cover and check the piston position compared to where the magnet runs past the pickup coil.

 

Take the time on your posts to spell correctly and use punctuation. It will help is to understand what your trying to say and help you in return.

[dajogejr]

it's called f'n troubleshooting- a bad habbit good mechanics develop :mad: a little bit of oil will temporarily make the reeds seal, and then you know there bad before you tear into them, since it started already and they got wet, you know to look elsewhere. have been doing this on sleds for years with a squirt bottle. the next step is to pour a capfull (a little more on small caps) of 2 stroke oil through the spark plug hole and barr it over slowly a couple of times to coat the pistons. if it starts after that, then you know there is a prblem there, cus not everyone has a compression gauge in their pocket.

 

 

My man....

I'm well aware what trouble shooting is....Any slight amount of oil will quickly get washed away with the slightest amount of fuel pulled from the carb. If not, you're not getting fuel...and sealing reeds with no fuel isn't going to amount to a hill of beans.

 

I agree on a capful of oil to coat the cylinders, not pistons, to try and get a better ring seal.

 

I've read a bunch of your posts...claiming a bunch of this so called knowledge, but you don't even know what a lockup clutch is???

 

He flipped the reeds around...both ways, no difference. So unless they're chipped or broken, it's not reeds.

 

Start by double checking all your ignition. You said it was lacking in power before you pulled the carbs....

Make sure the flywheel didn't move on the key, check your pickup gap flywheel to stator, ohm the stator, swap CDIs with a buddy's known working CDI.

 

120PSI is more than enough to start and fire the bike, unless you're at sea level with 17cc domes...

 

You might not be jetted cleanly, but your bike won't start. It's electrical...