I've been intending to start this thread for some time. Some of you will know what I've been doing so the time has come to open up to all. I know you all like plenty of pics, so I'll try to oblige as best I can.
The project started several years ago. I had a pile of 750 SOHC engine parts left over from my drag racing efforts and I was inspired to build a CR750 after seeing several pictures in various motorcycle mags and thinking I could do better. Well we shall see if that's the case.
I had all the parts to build a standard engine with the exception of a cylinder block, so I ordered one from a dealer, I'm think it was David Silver Spares, but not absolutely certain. Anyway the block was a new one, but I was told there was a slight bend in the top fin and hence it was on offer at a reduced price. The block duly arrived, the ding in the top fin was gently tapped back into place so you would never know it had ever been damaged and put to one side. Some time later I noticed that there was an extra cut out in the top for a cam chain guide and also additional cut outs at the bottom as well, such that the block would not trap the cam chain tensioner pivot. You CR gurus out there will know what this is, but it took me a while to find out that this was a genuine CR750 cylinder block. What a find!
A picture of a standard cylinder block is included below for comparison.
Continuing with the engine build the bottom end has a lightened and balanced crank by APE fitted with Crower rods. Mike Rieck was a great help in getting this done for me. Would you believe it was cheaper to buy a crank in the US, have it shipped over to APE to be worked on, shipped back to Mike and then over to the UK to me rather than have a similar job done to a crank I already had here in the UK. Two US dollars to the GB pound at the time may have helped, but even so. Anyway back to the plot. The keen eyed will have noticed the beefier primary chains and cam chain. The gearbox is a Nova close ratio affair. The usual heavy duty studs have been fitted and a K. A. Performance cam chain tensioner from Mark at M3 Racing.
Pistons are 62mm high compression items from Dynoman. 50 thou head gasket also from Dynoman. Camshaft is a Web Cam, 41A grind. The cylinder head has been gas flowed by The Cylinder Head Shop and fitted with a 5mm stem valve kit courtesy of Mike Rieck, a set of polished rockers (M3 Racing) and titanium tappet nuts from Voxonda (thanks Rob).
The last pic shows the whole caboodle in the frame
I'll come on to the frame later
Meanwhile the standard looking alternator cover, which I might add, has had about 30mm taken out of it to slim it down has since been replaced with an M3 Racing copy of the original CR750 part. The transmission cover as you can see has been suitably trimmed and that's about it for the engine. Well not quite, I shaved down the fins on the side of the cylinder head to be more like the original race bikes, but of course the cylinder head you see in the picture is the later type. However, that nice Mr Rieck has found an early head for me and is in the process of working his magic upon it (tee hee).
Much more to follow, but cheers for now
Eric
