Another vintage project from Great Britain, target Speed Week 2011

[thefrenchowl]

Hi Jeff,

That's the only document I have on various Model K spark timing, for the KHK, it calls for 31 degree std. I used to run a tad more with the twin carb DC Linkert manifold, around 33... KR run 36 basic...



I'm not too sure, but think methanol needs a bit more spark advance than gas, all the rest being equal, so I probably will start the same, 33 degrees.

A friend of Gordon has a roll on dyno, that's where we'll be heading 1st to sort spark and fuel settings...

Still needs to fab an oil tank, possibly a water tank and would really like a shallower fuel tank to get my head tucked in better but my metal bashing skills are next to nill/ziltch!!!

Patrick

[panic]

Way too many variables changed at once for there to be an easy answer.
The extra stroke makes piston motion faster around TDC (added spark), so does the thin air. Of course, the boost takes it back. I don't remember enough about methanol to comment.
The most common recco for H-D OHV engines with a second plug is to drop 5°, but I'm not sure how that interpolates with the SV chamber.
I have an .xls plot of piston position vs. crank rotation for the KH, LMK if you can use a copy.

Not really practical this late in the game, but a simple thin cylinder on each side of your nose with a connecting hose underneath gives a lot more room. Fill from the right side (for kick-stand), simple Schraeder air bleed on the left.

[octane]

Brilliant work, brilliant pics, brilliant post !
What more can one ask for !

I'm not too sure, but think methanol needs a bit more spark advance than gas

Yep

[thefrenchowl]

Jeff: The most common recco for H-D OHV engines with a second plug is to drop 5°

Yep, I have a 67 CH with twin sparks that was on electronic dual fire, it was most happy at 40 deg fixed advance... KH chamber is way better than the Sporty high dome, as proven by a lot less spark advance, so me think 5 deg less might just be a bit too much.

Lars: What more can one ask for !

I aim to please!!!  

I finally decided it's too much hassle to try to reverse the drive on the AMR500, I will spin it reverse, drive lobe on top as shown on the latest photos, so plenum chamber will be in front and carb at the back. This will either mean a convoluted inlet track with carb on the right hand side next to strut or carb stuck within the rear triangulation or straight rearwards facing carb with unaccessible float chamber!!! I will have a better idea on how to progress when the engine's back in the cycle parts...

All the best from Patrick

[thefrenchowl]

Hi again!!!

For the fuel tank, I'm looking at this shape:



This is a hill climb alcohol tank from a French racing TerroT bike from the 30s, holds about 5 litres and it's a beauty...

Sadly, can't find anybody willing to have a go at making a slightly larger replica, they all want a form to work from... Whatever happened to all the old skills??? An uncle of me wife was working in the body shop at Rolls-Royce in Crewe, about 5 miles from here... He was an expert metal basher with all his personal tools and dollies... He was made redundant and just thrown all his tools in the bin and sits at home doing sod all, what a waste...

Patrick

[thefrenchowl]

Hi All,

Last visit at Brian for a while,, the engine is now back in my garage for finalizing the built...

Brian started on the manifold hard bits, joining the 2"1/2 pipe to the nipples, t'will just need a bit of grinding/finishing to get a smooth transition:





I've sourced today a guy not far from me that deals in sanitary stainless pipe and fittings, he can get me a 2"1/2 elbow to run the pipe back to the supercharger outlet, should get that within a week...

Brian also machined the Ansin pulley, I wanted 2 pulleys, 2.25 to 1 and a smaller 3 to 1 ratio, but the second one would just be too small, no way to fit a nut on it!!!



I could have Brian made me a smaller one for the crank shaft, we'll see first how that one copes...  That'll be spinning the Ansin at slightly over 12,000 rpm for 5,500 on the engine...

I've got an all S/S iddler he made me some years back for a final chain drive that we will mod into a belt iddler, that will be fixed to an alloy plate in between the 2 pulleys...

Last week, we did measure the pop up, that was 60 thou of squish on the front head and 64 thou on the rear. Brian just skimmed the cylinder bases by 20 thou to get 40 and 44 thou of squish.

That's all for now, enjoy your week end, I know I will, putting back the empty engine in the frame to check tolerances between Ansin and frame...

Patrick

[38flattie]

Interesting to me, that the rear cylinder has more squish than the front. Would you happen to know the reasoning on that?

It's looking great Patrick- keep up the great work!

[wobblywalrus]

Patrick, it looks like you could cut a small sportster tank in half and add some steel in the middle to lengthen it.  That will give you that shape.

[bak189]

OR...you can contact Kent at Airtech in the good old USA......he has a tank the shape you are showing on the




OR....you can contact Kent at Airtech.....he makes a tank fairly close to the one on the French bike....

[bak189]

Sorry.....computors have a brain of their own.........................................................and much smarter then this old man..............

[Koncretekid]

It may be a little late for me to throw a monkey wrench into the works, but a thought occurred to me regarding your problem of driving the supercharger.  Would it make sense to turn the blower over, putting the drive side on the right, and running a jackshaft to drive it on the off-side?  That would reverse the direction of the rotors, and give you a wider selection of drive ratios.

[thefrenchowl]

38flattie: the rear cylinder has more squish than the front

Actually, more space on the back cylinder, so a bit less squish... Still, I don't think I'm gonna worry about 4 thou!!! Usually, there's more heat on the back cylinder, it might compensate a bit!

wobblywalrus: you could cut a small sportster tank in half and add some steel

It's not the length I'm worried about, just the height!!! That TerroT tank is about half the height of the Sporty one.

bak189: Airtech has a tank the shape you are showing on the French bike

... No spare cash!! I still will go and have a look...

Koncretekid: turn the blower over, putting the drive side on the right

I though long and hard about where to drive it from. From the timing cover looks attractive, but they were a load more problems to solve there, rear exhaust pipe is in the way, the oil feed to the crank goes through the timing shaft, serious mods to the timing cover...

The higher ratio of 3 to 1 was to see if I get as much umph as at 5500 while limiting the engine revs to about 4000 rpm to save on bottom end wear.

Patrick

[thefrenchowl]

Hi All,

Told you i was a bit worried about the clearances betwen blower and frame!!! Well, it just fits with very little to spare!!!





I will probably have to pull back the rear left foot rest as the clearance between my knee and the pulley is NIL!!!







Well, I'm off now to a small meeting for some bowling with a few club friends in Morecombe, about 100 miles away,

See you soon, all the best,

Patrick

[Koncretekid]

FYI: I wasn't talking about driving it from the timing side.  Drive the jackshaft from the primary side as you have it - the jackshaft crosses the crankcase and drives the blower from the right (timing) side.  It would be extra brackets, shaft, pulleys and belts, but then the blower is rotating the correct direction.
Tom B.

[panic]

I agree, it's pretty small, and has the advantage of allowing more ratio choices without changing the blower or crank pulleys - just use different diameter sheaves/sprockets/pulleys on the ends.