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Still going in the winter down there? Must be northern Aus?
Good going with the wins. Always a good feeling to get one over on a bigger bike. Says a lot about the rider.
I'm gearing up to leave in about 2 weeks for a 10 day, 2 race weekend in Michigan and Illinois late July/ early August. The Triumph is in good shape, waiting on a couple items for the B50 after it's skid across the track last month. If it's not ready, I'll bump the 650 into BEARS and see what happens....

Queensland Mike, although the piddly little circuit we were on is up in the Qld/NSW border ranges.
Was -1 deg on Sunday morning until about 8am.
After living here for over 20 years i have lost my pommie cold weather hardness.................
Best of luck with yours.
Nick

One of the races up at the goat track circuit last week.

https://www.facebook.com/groups/QEMSC/posts/2333949583405510/

Just a photo showing the simple end feed arrangement i use on a65's.
It maybe helpful if someone is contemplating doing the job.

https://ibb.co/y8Yvs3W

Harumph, only 20 years, standards old chap, standards. Don't let the natives drag you down, stiff upper lip now.
(runs and hides in a very dark corner!!!)

Sorry Phil, i'll try to do better......my wife thinks i'm turning into a whimp in my old age.

Well it's been interesting.................................. Matt and his missus have had covid
but thankfully are over it now and ok. The chap who has been doing a lot of the machining
and welding etc for us has had a heart attack and got over that..... We have had the
massive flooding etc so it's sort of good to get back on with the old girl. We've done a new
swinging arm and rear wheel assembly allowing a 145x16 car tyre to be run, looks great but
has meant that the rear suspension had to be changed which may mean slightly heavier
springs. I have been tasked with sorting the brakes out as they were pretty crap. It has 2 mini
SLS fronts using triumph 7 inch drums, they had been machined out rather too much so
we had to modify the adjuster setup to get them to work properly. New shoes and wheel
cylinders are on and after sorting out the cable operated master cylinder it's come together
quite nicely. Just waiting for some fittings to turn up. The rear uses a 2 LS mini front but
that's all new with the complete mini drum etc mounted on the new hub, once again waiting
for some fittings as i've replaced all the pipework with AN3 gear. The sidecar has a switchable
mini brake as down south they don't allow sidecar brakes on pre-62, it also now has a proportioning
valve to stop it locking the wheel up as it used to.
Hopefully we will get to the next meeting up at Stanthorpe again 9/10 April. Haven't had a chance
to do anything on the engines so we'll just use the 740 and see how we go, i went through the gearbox
and it seemed ok back in November, we shall see....................

See Nick, you just had to do some work on the outfit to keep warm!
Don't let minor irritations divert your attention.

Confession, I haven't touched the bikes yet, waaaaayyyy too busy trying to get the resto house (and new large garage) livable, management instructions you understand..........(and the management is an ex-TT and continental circus passenger, so best not argue eh!!!!!)

We seemed to dodge the rain you got Nick. Still some minor flooding. And I had a week at home last week with covid kids. Progress on my race bike is pretty slow. Waiting for the crankcases to be machined. Im now aiming for 2023 season 🤦🏻‍♂️

Better late than never Ben.........

So Nick question. Chris is using an A10 stroke but his crank is A65 welded and reground. My friend in Melbourne has a similar welded crank a bit longer stroke. His bike has a Big bore kit he made, (its beautiful), is around 920cc with head bolts moved. Std cam lifts valves 1/2" with roller rockers. It isn't slow.



But the question is how would strength compare with an actual A10 crank? Obviously welding done by someone skilled to get it right? They are obviously strong but would they be stronger than an A10?

It will be interesting to see what Chris gets on the dyno. I'm not even going to hazard a guess. I just hope it's more than he had before. And he can push that speed record up away from the Triumphs and 3s.

I wouldn't like to hazard a guess as to how strong it would be Mark.
I do know that many a10 cranks, like triumphs show cracks from almost
new. I suppose nitriding would help but having seen a few a65's let go
with a10 cranks i am a little suspect of using them. Offsetting the crank will
strengthen it hugely, welded or not.
The 13mm valve lift is the sort of figure i used to get with my old iron and
the cam fitted in that, tried to lift the valve to 1/3 of it's diameter. Makes
cam timing a problem as to valves kissing and piston clearance though.
If a sensible blood line is used the a10 crank should be ok, if it's a good one.............
The a65's shorter stroke inherently makes the crank stronger, as it's not
my bike or money, that's what i will use with Matt's one. As the guy doing
most of the machining is doing it free i can't really put pressure on him to
get the crank done, so the 80 x 74 offset motor will have to wait.

Hi

I would suggest that after the welding, they probably heat treated and nitrided the crank.

my tuppence worth

John

So one of these 74mm stroke 90s is 18lb 6.2oz, one like Ben's is 19lb 6.75oz compared to stock at 21lb 2.75oz.

Piston weights vary a little, Ben's Omega B44 are a bit heavier than JE B44 @ 391g. The 9.2 std 650 oversize for the racer are 415g. If they are a bit heavier than the Omega it's biasing it a little to smooth at higher rpm. If we put weights on at 614.7g to balance like the 734 which is /was smooth. Because the 650 works out at 621.8g and the 744 with JEs at 610g. though they need oil weight which would be a couple of grams? I might just do both around 614.7g because the 650 could end up with B44 pistons at some stage.

It would be interesting if Matt dynoed this outfit Nick. The head on Tom's stock Hornet added around 25.5% even if both readings are lower than expected.

Vizard has a chapter in his book about building hp that if you get the combinations wrong so they do not compliment each other, the returns are not good. And maybe that effects the Hornet with its straight through high pipes?

What you have seems to have those combinations very good, exhaust system and cam etc. Vizard tested 2 cams in a V8, one hot one recommend by a cam place and one he chose, which picked up 4%. Then the extractors, one a bit special with stepped headers and matching collector with a 12.5% increase. With 370ci small block ford hitting around 610hp.

Matt picked the bike up from me last weekend, i had done the brakes
and wiring. The brakes now need bedding in as they are all new, the wiring
was awful, a complete lash up!. I am wondering if the problems we had at
Warwick were due to it. As per normal the race meeting is a week away so no
time for me to set anything up or get it on a dyno etc. They love sailing close
to the wind those guys. I get a bit pi$$ed off though as if it doesn't run right,
it's down to me, i'm supposed to wave a bloody magic wand and sort it. Example
they had a brake 'expert' sort them out last time at huge expense, they were useless.
When i measured the drums, the shoes were nowhere near size etc.
I keep trying to tell them that with these old crates you can't just buy 'go faster' gear
and bolt it on and expect it to work, you have to dig into the reasons etc.
Anyway, i'll stop moaning for the minute, get over this weekend and run it up and see.
I promise you Mark, we will get it on a dyno within the next 6 weeks though even if
i have to do myself.

Dynoing isn't that important if it's running well, I'm just very curious. I hope it kicks butt.

I want to run it on a dyno to set the carb up properly anyway Mark.
This 'finger in the air' setup was too lean first up. They are lucky it
didn't nip the old thing up. It was showing signs of being very close
when i stripped it to put rings in yet it ran very well.
The other thing is doing a timing sweep to make sure we are getting
the best out of the burn. The only way you can do these things is
on a dyno really.

Well, it starts and runs on rollers ok but i wasn't game to ride
it around the streets to test it so we'll have to wait and see.
Looking like a few showers about for next weekend at the track
see how he gets on with the new rear tyre and frame mods.

Not a great weekend.....

What's good:
Weather was great.
Brakes are excellent, able to lock up with little effort at full chat.
Not a single oil leak. Well, until it broke anyway lol.

What's bad.....
Handling was off, frame needs a couple of mods. New back end has altered the 'stance' of the outfit.
Gearing was too tall now the box is speeded up even with biggest rear sprocket we had.
Gearbox still jumps out of 3rd. Maybe quadrant fouling on camplate or just the crap return spring arrangement.
Carb was better but still not right. Maybe needs fuel pressure regulator, strange as never encountered this before.
On checking up max 3.5psi is spec, i think we have more like 5-7. I think it's raising fuel level.
Arrived at this conclusion as smaller main jets and bigger air correctors gave better plug readings. Not what i expected.
Even used smaller acc pump jets to try to cure stumble.
This head seems to like a very lean mixture compared to my old ones but if fuel level is going too high it's hard to tell.
Fancy Ignition was picking up noise from fuel pump. Not really a big problem when running though.
Primary chain broke and took the case with it. (My fault,i didn;t check the tension, new chain and it had stretched then jumped
Crank nut had come off allowing sprocket to move on spline.) Wrecked the clutch basket and put a dirty great hole in the bottom
of the case and cover.
Just forgot as was concentrating on carb setup between races and practise sessions..

Dyno is now delayed until i sort/rebuild the engine again obviously.
I am bordering on a nervous breakdown!

The big norton was absolutely flying, don't think we'll be able to catch him now anyway.
He's just spent a bucketload of money on a billet crank, fancy cases etc. Plus he's sorted
the handling very well.

Sorry you are having trouble Nick. What brand chain is it? Old Reynold and Regina seem good. If the sprocket starts hitting the side plates it can break them or force them off. If you look at the old chain see if there are wear marks on the plates.

Was a Reynold chain Mark duplex blue box 82L.Endless.
Not the chain's fault, it was mine. Maybe the crank nut came loose first, i don't know.
It's down to me anyway as i should have checked it all after the first run/session.

Hi Nick

Sorry to hear of the troubles, hope you manage to fix it up.

John

Chain was a Renold not Reynold, they make steel tube. LOL.

A bit shorter then. Had the side plates been getting hit though?

I've not done a full postmortem yet as i had my head in my hands and was contemplating Hari-Kari.......

I'll let you know when i get the engine back but i suspect the crank nut
came loose, the sprocket moved on the spline and the chain then broke.
It wrapped on the clutch and punched through the case breaking the basket on it's way.