Upcoming Events
Jan
6
Sat
9:00 am Newark – CAROLE NASH CLASSIC BIK... @ Newark Showground
Newark – CAROLE NASH CLASSIC BIK... @ Newark Showground
Jan 6 @ 9:00 am – Jan 7 @ 5:00 pm
A kick-start to the new classic motorcycling year, the Carole Nash Classic Bike Guide Winter Classic returns to offer enthusiasts a chance to stock up ahead of a new riding season. Hundreds of trade stands[...]
Feb
3
Sat
10:00 am 38th Carole Nash Bristol Classic... @ Bath &West Showground
38th Carole Nash Bristol Classic... @ Bath &West Showground
Feb 3 @ 10:00 am – Feb 4 @ 5:00 pm
The Royal Bath & West in Shepton Mallet, Somerset, is the venue for the traditional Carole Nash Bristol Classic MotorCycle Show – an event that many deem as their favourite of the year. With a friendly atmosphere,[...]
Feb
25
Sun
9:00 am Cogenhoe Swap Meet @ Cogenhoe Village Hall
Cogenhoe Swap Meet @ Cogenhoe Village Hall
Feb 25 @ 9:00 am – 1:00 pm
The annual TR3OC swap meet where you can buy and sell triple parts.
Facebook
"

T160 misfire

Home Forums Main Forum T160 misfire

This topic contains 14 replies, has 7 voices, and was last updated by  Clive Allan 1 month, 1 week ago.

  • Author
    Posts
  • #6054

    Peter Lord
    Participant

    Just rebuild T160 everything new and I mean everything! Starts on button, sweet up to around 4,000 rpm but in top above that badly misfires. Tried different jets, tried new Boyer ignition, tried different plugs, new coils etc, but still misfires any thoughts what I should look at next?

  • #6056
    David Lord
    David Lord
    Keymaster

    Have you checked battery voltage/charging system when under load? Could be a lack of volts causing this. Otherwise what carbs and jets do you have installed? Have you been able to apply choke under the fault conditions to see what happens?

  • #6058

    Peter Lord
    Participant

    Hi David, new battery and charging ok. new Keihin carbs tried different jetting, still the same. Not tried choke yet. Away in Spain for a week was hoping to use T160 but reverted back to old T120!

  • #6059
    David Lord
    David Lord
    Keymaster

    Just a thought but how did you set the ignition timing if it won’t rev cleanly above 4K?

    Or, is there a fuel starvation problem, good flow from petrol taps, clear vent hole in filler cap etc

  • #6060

    Peter Lord
    Participant

    Checked the fuel flow, that’s ok, going back to basics when I get back and double checking ignition timing. Funny it runs really sweet up to around 4,000rpm then misses?

  • #6061
    Don Gray
    Don Gray
    Participant

    Vibration at higher revs causing the fuse in the holder to break contact or the ignition switch contacts? Check that the wire leads to the holder aren’t stressed & pulling the the contacts away from the fuse….I’ve had this on a T150V! Good luck…

  • #6062

    Peter Lord
    Participant

    Thanks Don away for a few days but will check everything when back!

  • #6066

    Martin Rawson
    Participant

    Check your earth circuit to boyer black box. Better would be to run the earth lead to the +ve earth on battery rather than through the frame etc.

     

  • #6067

    Peter Lord
    Participant

     

    away at the moment but will look at it when I get home!

  • #6070
    ian Bradshaw
    ian Bradshaw
    Participant

    Thinking outside the box. I used to rally cars and had a similar problem on a rally car. Only found the problem in the dark. The HT leads were very close together and tracking from one HT lead to another. The HT leads are generally close together as they pass the frame going to the plugs. At least this is easy to check.

  • #6071

    Peter Lord
    Participant

    Thanks Ian, it’s a thought, am away until next week but anything is possible. Will update if and when fault is found!

  • #6087
    Kerrin Gautrey
    Kerrin Gautrey
    Participant

    Hi Peter.

    I had a similar problem with my recently rebuilt T150. It was fine up to about 4,500 at a steady speed but any increase in load would cause it to missfire. All it took was an increase in gradient, running into a headwind or a handful of throttle & it would pop & bang. It gradually got worse on the way home from the Frech rally but provided I kept the revs below 4,000 there was no problem. When I dismantled the fuel lines I found the inline filters were full of fine debris, no idea what it is but the tank had just been repainted. Seems fine now, hope the tank is clean.

    Kerrin

  • #6088

    Peter Lord
    Participant

    Fault diagnosed to new Keihin carbs, they worked perfectly on my friends T160 yet on mine caused the misfire, very strange. No comments please temporarily gone back to Amals!

    • #6111

      Clive Allan
      Participant

      Hello, I had a similar problem with the Keihins. They were supplied with the wrong size main jets, (too big) the fuel overflow pipe inside each float bowl was bent, forcing the floats down, thereby not letting the float needle seat properly. I straightened the pipe, checked the float level, dropped down a main jet size to 110 (they had 115’s), checked the needle position (top groove). The pilot looks OK on yours, (probably 30) as it runs OK to 4000 rpm, which was the same on mine. When the main jets kick in, yours is running too rich. My T160 runs great now, the Keihins are very good. I use flat K&N filters with no issues.

  • #6109

    Peter Lord
    Participant

    Problem solved, Keihin’s don’t like air filters!

You must be logged in to reply to this topic.