New engine

Buellingvincent · Mar 30, 2022

Fritz race engine has a smaller alternator pulley mounded on the inside of a single sided belt and uses that as a belt tensioner at the same time.

Fast Eddie · Mar 30, 2022

mdt-son said:
What kind of stator is shown in #7 ? I thought it went inside the pulley, but your comment seems to indicate there is a second alternator driven by the outside belt teeth. Anyway, I see your point about differential thermal expansion. The clutch hub will heat up with a large time delay to the crankcase and a different CTO to boot.

Couldn't the stator shown be made to supply all the current needed for a bike? I like the idea of having it inside the pully. Where have a seen something similar - was it on a HD?

- Knut

I assume you mean the smaller stator lying on the bench in post #7 ?
I presume that’s the very fancy looking solution from Fritz shown in post #61 (which really does look clever).

My comments were about the mounting of an alternator in the standard Vincent dynamo position. The standard set up works fine with a sprocket acting on the outside of the centre of a triplex chain adjacent to the clutch drum. But when I tried the double sided belt version of this, it was not a success, and I believe this was down to the issues I mentioned.

Buellingvincent · Mar 30, 2022

mdt-son said:
118 Nm torque at 5300 rpm is a most impressing figure for a 2 valve engine. The power curve will remain high, actually it's rising all the way to 5800 rpm and probably well beyond. I am amazed! Tester probably ended the test at 5800 rpm to spare the freshly built engine.

For comparison, Triumph Truxton 1200 churns out 112 Nm @ 4250 rpm and it's an 8-valve motor w/EFI.

- Knut

Yes, the engine could probably produce a bit more power at higher rpm. The rpm limiter is currently set to 5800, valvetrain is calculated to work safely until 6000 plus some overrevving security in case of missing a gear.

Buellingvincent · Mar 30, 2022

Fast Eddie said:
Nice one Buellingvincent, you must be rather pleased to say the least!

Can you remind us of the spec you ended up with?

And what you’re going to do with it?

That chassis of Fritz Jr looks purposeful and tidy.

1330cc. 100 mm stroke and 92 mm bore. Terry Prince Top End kits. Nikasil coated alu liners in Terry Prince muffs. CR 10.8:1.
TPV MK5 cams and followers, slightly re-machined and DLC coated.
Godet Magnesium cases. Flatslide Mikuni TM40 carbs. Digital crank pulley triggered ignition system from Ignitech (Czech company).
Fritz own designed two-stage oil pump (in place where the magneto normally sits), piston cooling jets, separator with coarse filter in std oil pump hole.
Bob Newby clutch and double sided 40 mm belt primary. 5-speed Quaife gearbox and a Newby double sided Belt driven Clutch. Alton alternator.
Wide chainline kit (Plate G50 and chain sprocket). Gas breathing valve inside oil tank.

Buellingvincent · Mar 30, 2022

The oil pump as fitted on Fritz race bike. Same type is on mine now.

worntorn · Mar 30, 2022

Buellingvincent said:
Yes, the engine could probably produce a bit more power at higher rpm. The rpm limiter is currently set to 5800, valvetrain is calculated to work safely until 6000 plus some overrevving security in case of missing a gear.

Excellent result!
Mk5 cams?

Fast Eddie · Mar 30, 2022

Wow that’s some spec!

Hope you‘re gonna share the rest of the build progress with us?

Buellingvincent · Mar 30, 2022

worntorn said:
Excellent result!
Mk5 cams?

Yes on both! TPV MK5 cams and followers, but slightly re-machined by Fritz. According to him, Terry Prince did not make them exactly as Fritz had calculated using some special software. Both are now also DLC coated. Diamond-Like Carbon (DLC) is a process by a German company called Cewotec. Probably others do similar coatings.

Buellingvincent · Mar 30, 2022

worntorn said:
Excellent result!
Mk5 cams?

Thanks by the way!

worntorn · Apr 5, 2022

Buellingvincent said:
Yes on both! TPV MK5 cams and followers, but slightly re-machined by Fritz. According to him, Terry Prince did not make them exactly as Fritz had calculated using some special software. Both are now also DLC coated. Diamond-Like Carbon (DLC) is a process by a German company called Cewotec. Probably others do similar coatings.

I've heard that some of the Mk5s wore out very quickly, maybe that's why Fritz went with the coating.
Terry claimed that the MK5s he sent me tested RC 66, which is harder than stellite.
I took the engine apart to rebalance the crank at 1500 miles. The cams looked to be polishing up nicely, no actual sign of wear, nor should there be at 1500 miles.
I purchased a second set of these cams as they might be unavailable at some point in the future. I suppose that set could be coated if the first set gives trouble.
I can't see that they will at 66rc.
The good Norton cams are mid 50s RC, the soft ones more like 30rc iirc.

Buellingvincent · Apr 9, 2022

This is with another exhaust. A bit flatter power curve than the other.

Buellingvincent · Apr 9, 2022

Will pick up the engine next weekend, Easter.

And maybe some other parts…

Buellingvincent · Apr 9, 2022

High performance oil pump.

Buellingvincent · Apr 13, 2022

Will pick up the package now during Easter. At Fritz’s place.

gortnipper · Apr 13, 2022

How sexy is that?!!

Damn sexy!!

Buellingvincent · Apr 17, 2022

Tomorrow time to drive back the 2000 km. Or about 1240 miles.

Buellingvincent · Apr 20, 2022

Now finally my two projects in the same place

Buellingvincent · May 25, 2022

Some more parts for the build has arrived.

worntorn · Feb 15, 2023

mdt-son said:
118 Nm torque at 5300 rpm is a most impressing figure for a 2 valve engine. The power curve will remain high, actually it's rising all the way to 5800 rpm and probably well beyond. I am amazed! Tester probably ended the test at 5800 rpm to spare the freshly built engine.

For comparison, Triumph Truxton 1200 churns out 112 Nm @ 4250 rpm and it's an 8-valve motor w/EFI.

- Knut

The 112 NM of the Thruxton is at crank.
This 1330 engine managed 129 NM at crank! That is also slightly more torque per cc than the 1200 Thruxton. This is surprising as the Thruxton is a thoroughly modern engine designed to make high torque. As Knut mentioned, it has 4 valves per cylinder, efi and watercooling.
By comparison the Vincent is a dinosaur. Somehow it is slightly more efficient than the Thruxton. That says a lot for the design of the TP heads and the MK5 cam ( thank you Mercedes F1 team)

I think I know why the 1360 Vincent feels much stronger than the Thruxton R 1200.
It has considerably more power moving considerably less weight.

Glen

worntorn · Mar 16, 2023

Just for fun I factored Mr. Buelling's rwhp numbers by the SAE amount then plotted that against Triumph's own crankshaft torque graph for the 865 and 1200 Thruxtons.

The dyno test stopped at 5700 however the MK5 cams are designed to give max bhp at 6500 rpm.
It was mentioned that these MK5 s were reground and that this engine is going to be using 6000 rpm as max, so perhaps they are aimed at hitting max bhp at a bit lower rpm than with my setup?
That is rev limited at 7000 rpm, aim for a bit less as max.

New engine

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