classic motorcycle forum

Motorcycle Discussions => British Bikes => Topic started by: Paulo on August 17, 2009, 09:40:37 PM

Title: Bantam revs up when throttle closed?!!
Post by: Paulo on August 17, 2009, 09:40:37 PM

Hi.

I'm a newbee to brit bikes. Since my last run My Bantam D7 engine is running really noisy and aggresive. It knocks and bags and doesnt sound healthy.

  When the engine is ticking over and i open the throttle the engine revs but when i close the throttle it keeps on revving and reving very aggresively! The only way to stop this is to turn off the engine!

Please help!

 :'(

Title: Re: Bantam revs up when throttle closed?!!
Post by: bikerisme on August 18, 2009, 02:26:05 AM

hello check throttle cable is not sticking and throttle slide is closing you should be able to hear it closing with a click when it touches the stop i would try that first

Title: Re: Bantam revs up when throttle closed?!!
Post by: Dave Of Six on August 19, 2009, 07:04:20 PM

Thanks.

Have taken the carb off and given it a good clean. have also bought a new throttle cable and gaskets.

cheers for the advice

P

Title: Re: Bantam revs up when throttle closed?!!
Post by: Goldie on August 19, 2009, 07:09:34 PM

Bike running on a closed throttle.

Wish i had one of those. Think of the petrol i could save :)

Title: Re: Bantam revs up when throttle closed?!!
Post by: Paulo on August 20, 2009, 05:58:15 PM

Not really that cost effective. lol. I should have said it runs when the twist grip closed, not the throttle closed. but i'm sure the message got across :)

P.

Title: Re: Bantam revs up when throttle closed?!!
Post by: harry on August 20, 2009, 06:19:29 PM

Hi Paulo, years ago I had a similar prolem with a pre war James after much searching it turned out to be leaks in the induction system so check all the inlet joints are gas tight  by the way bad main bearing seals .if fitted, could also allow air into the crankcase.Good luck Harry.

Title: Re: Bantam revs up when throttle closed?!!
Post by: Paulo on August 21, 2009, 09:12:06 PM

Harry. Cheers. I have been suspecting air leaks and a guy in work mentioned these as well. I am just getting me head around the bantam engine. There is a knocking from the engine when it is running and there is a fuel leak at the bottom of the carb. I am gonna check seals etc tomorrow. thanks

P