Topic: Mating barrels to cases?

[tacc13]

Wondering if it's normal for the base of the barrels to not sit flush with the case prior to the head being stalled and torqued up. At the moment there is about a 2mm gap which I can't close. The crank spins fine, cam chain tensioner is in the right slots and I can't seen any obstruction on the surface of the crank case.

Thanks

[HondaMan]

Which engine?
The 750, for example, has 2 dowels on the outside front stud holes that stick out about 4mm, and their mating holes in the case is flared 2mm deep at the top: if the dowels are not seated then the cylinders are not fully set into those holes. It must be closed before you start torquing the head down, in any of the engines.

[tacc13]

Sorry, CB550F.

[HondaMan]

When that has happened to me before, it was because the cam chain's slipper tensioner's foot was not seated in the proper slot down at the bottom. It held the whole shebang up about 1/8" (3mm).

[tacc13]

Thanks, will go through everything again in slow time.

[tacc13]

Are the two oil control valves a press fit into the barrels? That seems to be the issue.

[tacc13]

Found the problem, there's a small amount of overspray from the ceramic coating in the oil control valve passage, stopping the valve from seating properly.

[DaveBarbier]

Those should drop right in with no resistance. Looks like you found the problem. Good idea to check the bottom of the tensioner though. Common mistake and very easy to do.

Read through this post to get a better idea.

http://forums.sohc4.net/index.php?topic=147178.0

[tacc13]

Thanks Dave, I wasn't aware that could happen.