Honda VTR1000 cylinder head trouble

By 26th August 2011 Honda, Road Bikes

Now we’re not prone to telling tales out of school, but as it’s the summer holidays just this once… this VTR1000 went to a local tech college for the students to work on. Its owner, a very nice chap, thought he was doing the best he could for the kids, and keeping his own costs down at the same time.

The cam chain tensioner had gone on the front cylinder, which is common on VTRs, and the valves had hit the piston. So the students’ job was to replace the valve guides, valves and valve stem oil seals which obviously includes recutting the valve seats.

The bike made its way to us, with the owner complaining of poor running. We put it on the Dyno and it was dreadful, so the first thing we did was check the cam timing; which sure enough was one tooth out on the inlet cam. Job done, we thought, so put it back together and back on the Dyno – still no good. So it occurred to us we’d better check the work that’d been done… and found incorrect shimming, valves not seating correctly and valve guides set at the wrong height. So we had to pull it apart, salvage what we could from the new parts used and put it back together properly.

Back on the Dyno one last time – it came in making 98bhp running like a bag of spanners, and left making 108bhp, as it should. The lesson here? Teacher needs new glasses!

Some detentions need dishing out for the headwork done to this poorly VTR1000...