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Tall gearing is probably better than low. The difference between the 654 and the 734 in one video. The 734 is short shifting and maybe 2/3-3/4 throttle. The 734 just does stuff so easy, so unstrained. It also handles 100% better even in a straight line. It actually accelerates fantastic. Wish I'd had this in the 1970s. This has baffled pipes as well. The baffle things bolt in and don't seem to effect power that I can tell. It doesn't struggle to get going.

After some issues the result was 2nd over the two days.

All effort now will be focused on the offset 750 short stroke engine
with the 5 speed box.

Ben's race motor will be a 671 90degree. If I put a data logger on the Firebird I can test it better and get data, then swap Ben's 671 in and test and dyno tune it with the data logger, plus put a bung in the exhaust and dial in the carbs. We can go big bore sometime in the future but it will be interesting to see what the smaller size can do.

What I have to do is work out getting oil into the crank. I can see where it comes from and where it has to go but do you use a small spigot and seal Nick? Is it in that case or something outside it?

When Matt drops the engines over, i'll take some photos of the
timing cover mods. Its just a top hat for the crank with a seal in it
the crank quill can be 8 or 10mm od and 4.5 id pressed in.
The pick up at the oil pump end is just a bush, the oil pump bolt
has an extended 8mm top with an o-ring which plugs into the bush.

I need to sort out balance weights etc for the offset so i'll email you.

Mark

I'll email you some photo's as well that you can look at.

regards

John

Thanks John.

So here is a great photo of the protagonists.



Chasing the big Norton with the 650.

Is that a 2 into one exhaust?

Yes, they link just before where the megga used to be, now
it's a sort of muted megga as we have silly regs now.

Interesting. I'm waying up what system to run on an A65 flattracker and a 2 into 1 Is readily available and cheap . I'm guessing not a lot in it performance wise?

PEH if you look at the video above I posted, that's basically a std A65 below the cylinder head and uses std '70 Firebird pipes mufflers and all, it's 21-47 gears so on a long track it would have legs. Instant grunt and I imagine wheel spin you may be able to control and use in flattrack. Being 650 means it would not hit as hard as a bigger engine and unless you are Mann or Aldana you probably wouldn't want it to. I would not use this frame and heavy stuff, But I expect you do not. If the tracks turn left both pipes are there if you deck it But they are up out of the way. Plus you can just buy them.

Mark, Strangely enough i already have the high front pipes in stock, It does sound well with great pick up on the video i have to say. Our tracks are all short 1/4 mile loose speedway except for Greenfield which is clay so good traction is key. The 750 Trackmaster i recently built has just under 50 bhp and 44 ftlbs of torque and goes well, the owner, rider loves it, he likes the old school 2 left side pipes and mega's, so he had some made in Titainium! more money than sense if you ask me, I will keep the high pipes in mind , i do like the look of them.