• Can't post after logging to the forum for the first time... Try Again - If you can't post in the forum, sign out of both the membership site and the forum and log in again. Make sure your COG membership is active and your browser allow cookies. If you still can't post, contact the COG IT guy at IT@Concours.org.
  • IF YOU GET 404 ERROR: This may be due to using a link in a post from prior to the web migration. Content was brought over from the old forum as is, but the links may be in error. If the link contains "cog-online.org" it is an old link and will not work.

To those who have set engine timing.

M

Motorcyclerider

Member
Member
When I attempt set the engine time I line up the crank to tdc mark. Then when setting up the cam timing it seems the exhaust cam timing mark is slightly above the top of the valve cover and the intake cam timing mark is slightly below the top of the cylinder head. I counted 36 chain pins from mark to mark. I’m not still sure if the timing is correct. The way I see it either the exhaust cam will timing mark will be slightly above the top of the head and the intake will be slightly below or vice versa. Not sure what is correct. I’ve timed many cars and are bikes but never had them with this discrepancy. The bike runs with the exhaust slight above and the intake slightly below. Runs fairly well. Any insight would be helpful.
 
Last edited:
Sounds to me like your timing chain is stretched.
Due to the rotation of the engine/cam rotation, a stretched chain would make both cams a bit late.
ie; At TDC the exhaust is slightly above the edge of the head and the intake is slightly below.
 
Yes I had that thought as well although it wasn’t new I used a chain from a parts bike. Seems like maybe it is ok then. Found a deal on some jd pistons 76 mm high compression. I’m going to build up one of my parts bike motors and when I do the top end I’ll put a new chain. I guess I could also take the measurement from the book. There’s a measurement to assess if the stretch is out of tolerance.
 
I'm guessing that your new pistons will require about a .080" bore.
If so, that would make the engine a 1052 but wouldn't require a special rod?

Ride safe, Ted
 
connie_rider said:
I'm guessing that your new pistons will require about a .080" bore.
If so, that would make the engine a 1052 but wouldn't require a special rod?

Ride safe, Ted
Click to expand...
Yes I would like to bore it to 1052 with compression pistons. I’ve done the hydrolock test and it passed but I still think my compression is weak. What is a normal compression reading?
 
You must log in or register to reply here.
Top