1991 DT100 Stall at low revs

[manxie]

I have a 1991 DT100 Suzuki that has become somewhat problematic at low revs / engine speed.<br /><br />Anything above approx 2000 rpm and it's fine.<br />Throttle is totally responsive and goes like hot stink, doesn't miss a beat !<br /><br />It's just miss-behaving at low revs...<br />cuts out !<br />sneezes !<br />slow to respond etc<br />Same in forward or reverse.<br />Makes it very difficult to manouver and coming alongside is a nightmare.<br /><br />Anybody got any ideas where to start looking ?<br />Mixture ?<br />Idle Speed ?

 

[jim dozier]

Re: 1991 DT100 Stall at low revs

Assuming that all the cylinders are OK (you said it runs well at speed) you probably need carb work (this has carbs right not EFI?). The sneezing suggests an overly lean idle mixture. If you are lucky you could try enrichening the idle mixture screw. More than likely you need to remove the carbs and disassemble and clean/rebuild them. Focus on the orifices, get a manual and set the carbs to specs.

 

[manxie]

Re: 1991 DT100 Stall at low revs

Many thanks for the reply jimd<br /><br />I have a manual and I've been working my way through it bit by bit. Yes it is carbs and not EFI.<br /><br />My investigations have been leading me towards the carbs. Never stripped a carb before but there's always a first time !<br /><br />I have readjusted the throttle valve sensor but the readings don't seem to return to a consistent value when you open and close the throttle on the oil pump control rod connection !<br /><br />I'd started thinking down the lines of maybe a worn out throttle cable that's preventing a correct return to fully closed position.<br />Is that a possibility ?<br /><br />For a starter I'll try going a bit richer and see if there's any improvement.<br /><br />Thanks to all for an excellent forum.