Another Suzuki that won't rev past 2800

[Chaps]

New to me DT140, 1988, appears to be fairly low hour engine. Starts & runs great, idles smooth as silk but won't go above 2800 rpm under load, seems to be stuck in "get home" mode but pushing the reset button does not solve the problem. <br /><br />I've checked and verified that the oil tank level sensor, the oil flow sensor and the water flow sensors are all working properly. The multi gauge on the dash is not indicating any problems at any time, even when the engine refuses to go faster, the water pressure gauge indicates plenty of pressure, the warning buzzer is turning off shortly after the engine starts per normal. Pee is strong.<br /><br />I suspected the CDI reset button, it checked OK. I then replaced the CDI reset module and the CDI itself from a good running engine but the problem persists. I ohm meter tested the coils under the flywheel and they all check out.<br /><br />Any suggestions or other ideas? Thanks in advance - Bob

 

[leftofcentre2006]

Re: Another Suzuki that won't rev past 2800

Had the same prob and symptoms as yourself on my DT85.<br /><br />After almost having the Lifeboat out and then getting an engine specialist to visit my home, it turns out at some point the engine had been starved of oil and the Big + Small End Bearings had worn to excess.<br /><br />Is there any knocking from the engine when revved up?<br /><br />What are the plugs like?<br /><br />Try removing each one with the engine running to see if all cylinders are fireing.

 

[Chaps]

Re: Another Suzuki that won't rev past 2800

Thanks Andrew, plugs look fine and no odd sounds coming from the internals. I'm almost certain this is an electrical problem, I'm going to do a cylinder drop test as well as check the compression tomorrow.