Loving the look of that frame Alan. It seems a shame to hang anything off it. Why not just put on some pedals?
My wonderful wife overheard a conversation about my racebike. I have been offered a free paintjob and want it in it's original Deuce colours, as raced in Pro Stock by Pip Higham. She ran upstairs and found a copy of Superbike magazine from December 1980.Hopefully here is the front cover; Wait till you see the centre spread!!!
Well it was raining all day today , so I completed a job on somebody else's carbs and then started work on the racebike cylinder head. Gave it a quick clean with a plastic fibre wheel in my drill. Cleaned up the exhaust threads. Then before I removed the valves, I thought I'd check how well sealed to the head they already were. I poured paraffin into the inlet and then exhaust ports and then checked the combustion chambers. No paraffin at all. I removed the paraffin and then thought I'd have a look at the valve seats anyway. I found the valve spring compressor that I'd bought 30 years ago to work on my original sprint bike. Sure enough, the valves had recently been lapped to the head. Saving me a normally laborious job.
With the inlet valves out, I felt around the area where the valve seats meet the head and there was a ridge on both valve ports. I set up my Dremel type tool with it's flexible drive and ground the seal and head until there was no step all around it. Was going to clean up the casting marks in the inlet ports , but it's already been done! I know I should grind the tops off the valve guides and blend them to the head, but I'm not that skilled with the grinding tools and I don't wanna risk doing any damage.
Excuse a maybe stupid question Al' but do you still lap the valves by hand or is there now a doohickey for that?
i have a doohickey mate. Put one end in an electric drill, sucker on the other end. The doohickey oscillates if you hold the middle part of it while the drill spins. Takes about 30 seconds per valve instead of 10 minutes. Think mine were machine lapped because the faces are a bit too wide, but I can't afford £100 for 3 angle valve seat cutting.
You are special though Ken. Had a bit of time in the garage today. I donned my thermals and decided ,with a bit of encouragement, to grind the tops off the valve guides and blend them into the head. Mainly used small emery tubes on my Dremel , but had to resort to small grinding wheels at one point to remove enough steel from the valve guides. A bit more work to do , but I was sneezing too much and my snot was freezing on the end of my nose. Managed to blend most of the ally around the stems , but need a bit more alloy removal before they're finished.
It's usual mate. Standard heads have a lot of restrictions to good gas flow. Rough castings, valve guide ends, wide valve seats, over engineered valves. Usually worth doing after fitting big cams and big carbs when it makes a big difference. I can't afford either, so I thought I'd try some fairly cheap mods that may make a difference, logically?
