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Running up after fitting new cam etc, old moron tweaking the carb........
https://www.facebook.com/matthew.tyson.5621/videos/1672662059601228

Hi Nick

Sounds sharp.

John

Hi John

Motor seems quiet sweet, much quieter as far as top end noise is concerned.
I've fitted one of my ignitions on so i can change the timing map, uses the Boyer or pazon trigger
setup. Wants a sharper advance curve i think. We'll test and set it up at the track in April.
Just have to remember to take my laptop.........

Nick

Took a good look at it, a lot to see there...

Sorry about the feet....................

Yes--you need to wash them more often than every other leap year! (Brit humor).

P.S. -- sounds really nice.
All the Brummie boys would have been proud of you----

Hi Nick

Look forward to a clip when your track testing. Yeah, toolboxes now aday's need to come with a compartment for the laptop.

John

No worries, i'll get Matt's wife to video it. I may even take it 'round for a few laps myself
if my wife lets me.... It's only a club weekend meet so pretty layed back. It's not as if i'm
going to try and win is it????

LOL, I'm reminded of when my brother came up to Nova Scotia to take the Kawasaki High Performance Riding School, at the end of which they held a parade of all the participants. My brother "won" the parade by passing everyone including the parade Marshall. The organizers were p*ssed and they bawled ME out as he was riding my race bike (a lowly CB350 Honda)! I was ecstatic and had to bite my tongue not to tell them where to stick their complaints. After all, he'd obviously succeeded at the finer points of "High Performance Riding!"

Tom

That damn red mist.................................

Great to see another Brit on the track. Sounds good but def would like to hear it when it's angry!
Reminds me of the Moto Giro I rode in. They said it's not a race. Yea....

No apologies needed. I'm always wearing flip flops too. (California thing?)

Nice outfit, Nick--- I see the outcome of a lot of experience and the avoidance of a lot of mistakes built into it!

Thanks Richard, i found these photos on my phone and remembered that Kevin
wanted to see a couple. The exhaust/silencer on it at this time would set the noise
meters off as it was a very sharp/harsh note so i put the larger exit bottle shape
megga type on which is right on the limit but gets through.
It, of course meant considerable carbonation changes.

Do you have just the one breather Nick? I have done the timing chest one like yours, and have one in the centre of the rocker cover, which i think will need a deflector/ guard over it inside the cover, as im getting a fair amount of oil in the catch tank for not many miles, although i doubt the rings are bedded in yet which may contribute. I don't have the timed cam breather in but i have fitted a pipe from the exit into the catch tank for a little extra breathing, also, have you experimented with non-return reed type valves in the breather pipe. Have fond memories of seeing Chris Vincent flying round Mallory on his Bsa outfit, amazing to watch coming down the Elbow with a drift going on.

The primary is used as a plenum the timed breather is blocked off.
That 3/8 pipe is the only breather, it seems to work fine. Never used
a reed on any of my race engines but all breath into the primary so
much larger expansion area.

Mallory was a great circuit, better before the silly 'bus-stop'. Had heaps of
fun there.

Mallory was my local track-- I lived about 15 miles away in Rugby.
In my early days used to ride there with friends--the ride there was quite fast but the return ride after being inspired by the racing was pretty hairy.
My favorite spot to spectate was on the exit from the hairpin--you could see the bikes coming up to the hairpin and the outfits drifting around the hairpin before drifting into the Elbow.
Worst sight was when I was spectating from the entrance to the hairpin--Fritz Scheidegger had brake problems and didn't slow down or take the hairpin--went straight on, hit the top wall of the hairpin and was thrown high into the air like a rag doll. Terrible loss as he was a really good rider.
Ah well--life goes on!

Absolutely, my favourite circuit (pre bus stop!), a circuit people tended to rush at, rather than understand and work with and get rewarded.

Nice outfit (even for a BSA - only joking), seriously was nearly a tickover.........
What and when did you race in UK?

'75-76 morgo triumph then 90-99 bsa powered always the same old outfit bought in 74.
Came here in 99 ran for another couple of years with the beezer. Sold it a couple of
years ago now, shoulders and back are a bit knackered.
https://imgur.com/ywX7KIT

I still preferred Cadwell Park but only raced on the large circuit once, most of the club
and crmc stuff ran on the shortened variant.

Do you have to wait till the club day to test it Nick?

What is it balanced at? Factory tested and found 56% for racing. The Firebird would be 70% and vibes especially in the bars get intrusive at rpm. Though it's smooth up till 4,000 pretty bad by 6,000 or 7,000. Shame the factory never fixed that.

G'day Mark
We'll runit up again and pull the head down , do tappets etc before the meeting but
we don't really have anywhere to test it and i don't like just running it for long as it needs the
rings bedding in.

I took a flyer at 60% and it seems to be quite good, Matt doesn't think it's any worse than the
650 he had before. His passenger thinks it's smoother. You have to consider the fact that most
races are so short now the blokes can stand a few vibes. You don't get many 8-10 lap heats with
15 lap finals anymore. In the historic series many of the bikes and a lot of the riders couldn't do it.

Yea, factory said between 55% and 60% made them smoother around 6,000. Bit rougher down low. So after all their work, production stayed 70%. They did all this in the 1950s as well.

It's funny the effort they went confirm what they already knew. Even to drawing and casting OHC heads knowing they could not produce more power, nor be as reliable. When they could have been addressing real improvements worth introducing. Chasing OHC catch up tech, rather than bullet proofing, actual smoothness, discs, 5speeds and hp which would have placed them ahead.

The Firebird has a very sharp sound and a fierceness on full noise that's not normal. I think the clutch is finally just about coping. I cut half the linings off so they are narrower. Having trouble getting the nice valves now because of virus.

I wonder how the factory would have done a 90, still using a bolt on flywheel perhaps?

I have one mostly done just needs counterweights on the flywheel, grinding and rods and balancing and have a 473cam to suit. Reading about the factory just makes me want to try stuff and see what might have been possible.

We had a 90degree 650, big pipes big valves and 38mm TMs it had very good top end, and went from about 5,000-9,000 like a switch when you got to 5,000. It would work at low rpm but not like the 34mm head which is more like having the cake and eating it.

I hope this cam has the outfit going as well as before, or better.

Yep was there Trident Man, standing where the Bus stop is now, I heard the bang then saw Fritz and John Robinson go over the top of the crowd on a built up embankment, Robinson survived, but broke just about every bone he had, The picture is still in my head. I lived 4 miles away at the time, when the wind was in the right direction we could here the engines, it had a certain draw to it, my brother and i would cycle down a Drovers track just following the noise, the chap on the gate would let us in as we didn't have a penny to our names, saw Ago on the MV's, Hailwood on the Four's and Six's, awesome sound.