Suzuki 2 Strokes

Hi all, i was riding home a few days ago and the bike would not accelerate with the throttle open in anything above 1st gear. seems to be bogged down or something? i thought maybe it was dirty carbs but now i am thinking it is something with the mixture being too rich? it seems ok in 1st gear but once you go into second and open it up, it barely moves. any opinions?

thanks

ps- i did change the air filter a couple of rides ago but rode it without problem twice before this.

Do you smell strong odors of gas when it's idling? 0r hard starts ? If not, then it's not running rich. It could be several other things. I would check the level of charge on the battery. If the battery is not flly charged. Believe it or not the bike will have the exact same symptoms. If a battery is dead or low on charge the bike will not recharge the battery like a car would. Which many people tend think. I would start there. Then plugs, coils, rectifier and stator. It sounds like a charge issue. My bike was acting exactly the same a few weeks ago and. I thought my fuel filter was over clogged, but after looking further. The battery was dead. Charged it and the problem went away. And that was many miles ago.

Thanks mate but the battery is strong and the charging system is good. using electronic ignition so that should be fine as well as i am getting good spark. plugs look a little black but not wet. air filter is made of different foam than before, could that be it or is it just dirty carbs? will take the carbs off tonight and clean them.

Yes, the carbs are the next thing I'd look at. Did you remove the filter screen at the bottom of the petcock? If your tank has rust of any amount check that and of course a jet in the carbs can be subject to that issue. Is the bike hard to start and how does it idle? Try adding a stock filter. If the current one is home made and of a different density. Absolutely that could be the cause. Some filters look exactly the same, but can be quite different in how much air passes through one compared to the other.

PJ, thanks mate, had a look at the carbs today and they are spotless! must be the filter material. i will try something thinner and see if it changes. these old bikes sure can be a pain. thanks for the help

MikGsxr wrote:PJ, thanks mate, had a look at the carbs today and they are spotless! must be the filter material. i will try something thinner and see if it changes. these old bikes sure can be a pain. thanks for the help

Just because they look spotless, doesn't mean they are. There may be a tiny particle of something in a jet. You have to properly inspect all of them. Yeah, I love these old bikes. But, the downside is......... they are very high maintenance. Filthy pigs that are near impossible to KEEP clean. Heavy, rough on gas and something always needs tweeked. I know you said that its not electrical, but did you properly check the points ?

Do I understand that it was OK and you changed the filter and it's no longer OK - in which case it's probably the filter. If the old filter is NLA, just remove the filter and ride to the end of the street. If it's back to its old self get a new filter.

If that doesn't fix it, check for flow from the fuel tap (petcock).

Double check the battery voltage NOW just in case it WAS good but something broke.

Thanks guys, put the old filters on and it is back to riding fine! it is amazing how what looks like better flowing foam is actually more restrictive! next step- getting the slides to move at the same time. they seem to be off. the idle screw on the right side does not seem to do anything either? you can hear the left slide click when you open and close the throttle but no noise from the right side?

Good to hear. As far as the slides are concerned, remove each diapram spring. Lie them flat on table and measure each one. One spring may be weak compared to the others. Or you have contamination affecting the slide. Check diaphragm for rips and that it seats properly.

I got some Uni-filter material from Dennis Kirk and made a pair for my GT500. Following the instruction sheet that came with the material, in a few minutes I was done. I let the adhesive cure overnight, oiled them and installed them like factory. Runs just fine! Do check the foam on the floor of the air filter box, it may need to be replaced with something else to seal it.