Upcoming Events
9:00 am CAROL NASH CLASSIC BIKE GUIDE WI... @ Newark Showground
Jan 5 @ 9:00 am – Jan 6 @ 5:00 pm
A kick-start to the new classic motorcycling year, the Carole Nash Classic Bike Guide Winter Classic takes place on January 5-6 at Newark Showground. It offers a welcome respite from the hectic holiday season and[...]
9:00 am 39th CAROL NASH BRISTOL CLASSIC ... @ The Royal Bath & West Showground
39th CAROL NASH BRISTOL CLASSIC ... @ The Royal Bath & West Showground
Feb 2 @ 9:00 am – Feb 3 @ 5:00 pm
What’s on From humble beginnings in 1980, the show has grown and evolved into Britain’s greatest annual celebration of all that is best about the motorcycles of yesteryear. The event is a magnet for enthusiasts,[...]
9:00 am Cogenhoe Swap Meet 2019 @ Cogenhoe Village Hall
Cogenhoe Swap Meet 2019 @ Cogenhoe Village Hall
Feb 24 @ 9:00 am – 1:00 pm
Cogenhoe Swap Meet 2019 @ Cogenhoe Village Hall
MEMBERS ONLY FREE EVENT Come along to the Cogenhoe Village Hall for the superb Swap Meet. Free Tables available for you to sell your spare triple parts and there will be lots available for purchase.[...]

valve clearances

Home Forums TR3OC Members Forum valve clearances

This topic contains 5 replies, has 5 voices, and was last updated by  Angus McLeod 4 months, 1 week ago.

  • Author
  • #7303


    I have just reassembled my t150 after a rebore, and some other work, which involved taking off the timing wheels. and I now appear to be struggling to get the engine to turn over without the kissing the pistons. The timing marks are as the workshop manual . I have used a copper head gasket, and copper rockerbox gaskets, as usual, but the only way I can get it to turn over with a spanner, is to undo the valve clearances to a massive gap. The cylinder head has been skimmed down by previous owners almost to the limit, is this the problem ??

  • #7304


    Hi Ian.

    I’m sure someone with more experience & knowledge will be along soon, but the first thought that occurred to me is if you’ve had work done on the head have the “right” valves been put in? I can’t remember which way round now (doh!) but late & early model valves were different lengths. Ie have you put long valves in where short should be fitted? Good luck, cheers Don.

  • #7305


    Hey Don

    That could be a possibility. I am not too sure of the difference in length of the early and late models. It sure is annoying to think the head has to come off again !!



  • #7306
    Kerrin Gautrey
    Kerrin Gautrey

    Hi Ian.

    You say that the timing gears were taken off, are you sure that the valve timing is still correct?

  • #7309
    iain strong
    iain strong

    Ian, late T150s had short valves with long adjusters and early vice versa, but it does sound like the valve timing could have slipped when timing cover was off

  • #7310

    Angus McLeod


    Putting long or short valves in wont make any difference to your problem; it would just make getting the correct clearances impossible.

    If you have some big cams in it is possible that the original pistons had the valve cutaways deepened to give clearance and your new ones haven’t. Other than that it must be the valve timing.


You must be logged in to reply to this topic.