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Rode my sons 95 this weekend....doesnt run veey well in 1st n 2nd gear at any throttle position. Soon as i get it into 3rd it runs awesome, great pull...wondering what could cause this? He told me that its been like that for months and that hes just adapted to it that way. Carb is squeaky clean new jets...could a failing jet block do this? Worn slide or emulsion tube? suggestions

What is the gearing (front and rear sprocket sizes)?
I'd also check the air filter, to see if it's clean as well as the reeds to see if they are leaking/not sealing/chipped.

6 Riders wrote:What is the gearing (front and rear sprocket sizes)?
I'd also check the air filter, to see if it's clean as well as the reeds to see if they are leaking/not sealing/chipped.

13 /49 im pretty sure. Reeds are realitively new...few months old. Will check them. Filters good. It runs as if its loading up in first n second. In any other gear at same throttle pisition its fine...lofts front easily...great excell.

Can you WOT it in 1st/2nd gear? Or does it bog out before you get there?
Did you (or anyone else) clean the carb recently? The #1 reason for the jet block gasket. Usually causes problems opposite of your description.
If you changed the reeds, did you get the carb boots sealed properly? Sometimes the boots don't get all the way on or fold and they don't seal. This would cause a lean bog as to much air is introduced. How about the reed block gaskets?

6 Riders wrote:Can you WOT it in 1st/2nd gear? Or does it bog out before you get there?
Did you (or anyone else) clean the carb recently? The #1 reason for the jet block gasket. Usually causes problems opposite of your description.
If you changed the reeds, did you get the carb boots sealed properly? Sometimes the boots don't get all the way on or fold and they don't seal. This would cause a lean bog as to much air is introduced. How about the reed block gaskets?

I cleaned the carb last 20 times...lol. Boots are sealed up good...after i assemble topend, installed new reeds...did a leaktest it past. Yes, it just never seems to open up or clear out in first or second..

Jet block gasket?

Did you check the floats? Possibly too rich for low loads of 1st and 2nd.

argclh6670 wrote:doesnt run veey well in 1st n 2nd gear at any throttle position. Soon as i get it into 3rd it runs awesome, great pull...

argclh6670 wrote: It runs as if its loading up in first n second. In any other gear at same throttle pisition its fine...lofts front easily...great excell.

I am going to go in a different direction from everyone else on this. I wonder if something is up with your transmission? The engine, carb, jets, etc don't know what gear you are in. So if the bike doesn't run well at all in 1st and 2nd and then suddenly runs great in the higher gears, maybe something is binding with 1st and 2nd?

If it were me, I'd put the bike on the stand and get the rear wheel off the ground. I'd pull the clutch out so the transmission isn't connected to the crank. Then I'd spin the rear tire in all the gears to see if 1st and 2nd don't have an excessive amount of drag or feel drastically different than all the high gears.

It probably isn't the transmission, but I just can't wrap my head around what else would cause a night and day difference once you shift from 2nd to 3rd.

Tedh98 wrote:

argclh6670 wrote:doesnt run veey well in 1st n 2nd gear at any throttle position. Soon as i get it into 3rd it runs awesome, great pull...

argclh6670 wrote: It runs as if its loading up in first n second. In any other gear at same throttle pisition its fine...lofts front easily...great excell.

I am going to go in a different direction from everyone else on this. I wonder if something is up with your transmission? The engine, carb, jets, etc don't know what gear you are in. So if the bike doesn't run well at all in 1st and 2nd and then suddenly runs great in the higher gears, maybe something is binding with 1st and 2nd?

If it were me, I'd put the bike on the stand and get the rear wheel off the ground. I'd pull the clutch out so the transmission isn't connected to the crank. Then I'd spin the rear tire in all the gears to see if 1st and 2nd don't have an excessive amount of drag or feel drastically different than all the high gears.

It probably isn't the transmission, but I just can't wrap my head around what else would cause a night and day difference once you shift from 2nd to 3rd.

i was having a hard time too...my son would say its only 1-2 but rest are good...id tell him that makes no sense beings it doesnt matter what gear its in....its all throttle position/carb. Until i rode it...
I will check the tranny...doesnt seem to be bindinding nor dragging.

CAL-kawi wrote:Did you check the floats? Possibly too rich for low loads of 1st and 2nd.

Ive been thru carb numerous times....cleaned, set float heights, rejetted. IMO it shouldnt be be too rich at current settings. Couple things yet to do in the jerting dept to try though.

Julien D wrote:Jet block gasket?

I syppose its possible? I do have a couple on shelf...definitely on my list to swap.