New monoshock space frame

jseng1

jseng1

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Just got these photos of a newly completed monoshock space frame and low vibration motor.
New monoshock space frame

New monoshock space frame


with fairing
New monoshock space frame
 
It looks as though the motor could be moved about an inch further forward. It depends on how it feels in corners when you gas it at the transition point. It might be too light in the front.
 
It just came together. I'm sure there'll be a few adjustments starting with megaphone heat shields. The photo below shows heat wrap that worked for Ken Canaga's monoshock with Rob Tuluie riding.
New monoshock space frame



Here's the pipe heat wrap on the original version when I was racing.
New monoshock space frame
 
jseng1 said:
It just came together. I'm sure there'll be a few adjustments starting with megaphone heat shields. The photo below shows heat wrap that worked for Ken Canaga's monoshock with Rob Tuluie riding.
New monoshock space frame



Here's the pipe heat wrap on the original version when I was racing.
New monoshock space frame

marshg246 said:
Does it come with asbestos pants? :D Those look some mean leg burners!
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That looks OUTSTANDING!! What a piece of Art.
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This frame took 3rd place at the Willow Springs Battle of the Twins AMA national road race with Rob Tuluie riding against a field of monoshock Ducatis in 1990. I don't have a vid of that race but here's one a few years earlier against some monoshock Ducatis. It didn't help that I had biased tires instead of radials and a 4 speed instead of a 5 speed as did my competitors.

 
It seems to be a copy of that frame from the 1980's which looks loosely based off the Ducati 600 TT2.
Why does it not have a lowboy fuel tank ?
Based on the front suspension travel the steering head could have been a good (50 mm / 2 inches) lower.
Given all that work it could have also had an eccentric swingarm pivot to tailor anti squat/arm angle of around +/- 9 degree's or there abouts (iirc).
( I do notice the crankshaft is inline with the axle plane.)

Just observations, not criticisms given the vertical cylinder on the TT2.

Ducati-Heritage-modelli-moto-600-TT2-banner-full-1330x600.jpg


I remember back in the 1990's building a lowboy aluminium fuel tank for a then new GSXR600 race bike, the owner getting a Carbon Kevlar cover (a shell that looked like the top of the stock tank to cover it)
 
1. That looks like a very short-travel shock unit. (just sayin')
2. I wonder why nobody has built their own "square" profile fork lowers, just for grins. Inner bore round, of course. They'd kind set off the lines of this bike well, I think.

Very cool bike.
 
Time Warp said:
It seems to be a copy of that frame from the 1980's which looks loosely based off the Ducati 600 TT2.
Why does it not have a lowboy fuel tank ?
Based on the front suspension travel the steering head could have been a good (50 mm / 2 inches) lower.
Given all that work it could have also had an eccentric swingarm pivot to tailor anti squat/arm angle of around +/- 9 degree's or there abouts (iirc).
( I do notice the crankshaft is inline with the axle plane.)

Just observations, not criticisms given the vertical cylinder on the TT2.

View attachment 112043

I remember back in the 1990's building a lowboy aluminium fuel tank for a then new GSXR600 race bike, the owner getting a Carbon Kevlar cover (a shell that looked like the top of the stock tank to cover it)
Click to expand...
Yes it was absolutely inspired by the Ducati TT2. I measured up a TT2 and went from there. The swing arm had to be housed in a section of 1/2 round tubing to get the pivot forward enough (heavy wall tubing cut in 1/2 the long way). It was originally designed for 18" wheels but 17" wheels with radial tires work best. I remember that I could push it into the begining of a slide where the tires would start to skitter on the pavement and just hold it there through the turn. It handled like a dream. There were a lot of innovations on this bike as described in my innovations page.
 
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Time Warp said:
It seems to be a copy of that frame from the 1980's which looks loosely based off the Ducati 600 TT2.
Click to expand...
Perhaps Jim didn't make it clear that this is indeed a copy of his original monoshock frame from the '80s. Some years after I bought the bike from him, he put together a detailed package of CAD drawings and pictures, available from his website, for anyone wanting to duplicate it. This bike was built from those plans.

This is a collage of pictures of the original bike at Daytona in 1990, showing a bit more detail. Note the large battery mounted to the front of the engine. We had to add weight to meet the minimum AMA limit for the class, so we used a large battery and located it there to see if it did anything for the handling. The rider, Rob Tuluie believed it did improve the turn-in ability slightly.

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It is possible that moving the engine forward slightly might be an improvement. As Jim pointed out, he originally designed the bike for 18" tires, which require more clearance. But I think we achieved pretty much the same by fitting the added battery weight (lead-acid, of course, no LiFePo4 batteries back then:)).

In any case, it was a lovely bike to race. And, as Jim mentioned, it was the last Norton to take a podium position on an AMA National road race. Must have got something right.

Now I'm feeling guilty because I tore it down to refresh several years ago, and still haven't got it back together. That seems to be a pattern for me lately.

Ken
 
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Generally speaking, and within reason if the bike handles OK, the rider can adjust to it. I did not know until I rode a genuine Manx Norton what handling could be. I never thought about transition points in corners and oversteer or understeer. I just accepted what the bike did and rode to suit. I know with my 500cc Triton, until I moved the motor forward as far as possible, I could not ride it. When I built my Seeley 850, I positioned the motor as far forward as possible without being stupid. When I looked at the space frame bike, I noticed the short distance between the motor and gearbox. You would find out whether it handles when you gas it at the transition point and progressively advance the transition point. A lot of guys do not seem to do that. It probably only matters on short circuits.
 
The only problem with this frame is that there weren’t enough of them built. Pete Clancy is helping with that. You can always adjust the fork yokes to a lower position – until you run out of ground clearance. You can see that the engine is towards the front and the bike is front weight biased. Compare the photos to the engine/crank location of a to other Norton frames.

See the new video I pieced together from what Pete Clancy sent me. Check the quick rev at 1:39

 
1:39 sounds about like my little 750. lol

What cam is in that motor? Lumpy idle. I like
 
lcrken said:
Perhaps Jim didn't make it clear that this is indeed a copy of his original monoshock frame from the '80s. Some years after I bought the bike from him, he put together a detailed package of CAD drawings and pictures, available from his website, for anyone wanting to duplicate it. This bike was built from those plans.

This is a collage of pictures of the original bike at Daytona in 1990, showing a bit more detail. Note the large battery mounted to the front of the engine. We had to add weight to meet the minimum AMA limit for the class, so we used a large battery and located it there to see if it did anything for the handling. The rider, Rob Tuluie believed it did improve the turn-in ability slightly.

View attachment 112052

It is possible that moving the engine forward slightly might be an improvement. As Jim pointed out, he originally designed the bike for 18" tires, which require more clearance. But I think we achieved pretty much the same by fitting the added battery weight (lead-acid, of course, no LiFePo4 batteries back then:)).

In any case, it was a lovely bike to race. And, as Jim mentioned, it was the last Norton to take a podium position on an AMA National road race. Must have got something right.

Now I'm feeling guilty because I tore it down to refresh several years ago, and still haven't got it back together. That seems to be a pattern for me lately.

Ken - When I made that comment about the position of the motor, I was not criticising, it was simply an observation. I always believed the best way to get around a corner fast was to brake into it right up to the middle which would be the transition point, the start accelerating out without rolling any distance in the middle. However I discovered that if the bike is difficult to tip into corners, it also tended to run wide as I accelerated out of the corner. When I changed the trail by shoprtening the yoke offset, I was able to change from braking to accelerating, just inside the corner. The result is, I can accelerate at full throttle from just inside the corner, right through it and up the next straight. My bike is not the fastest accelerating, but it comes out of corners going extremely fast, and other bikes which do not start accelerating so early corners need heaps more power to pass me before I reach the ends of the straights. The weight bias is extremely important - it needs to be well forward. If the front goes light as you accelerate out of corners, it is easier to lose it. If the bike feels stiff as you tip into corners, it will usually tend to run wide as you accelerate out - understeer ! If you have 19 inch wheels, that slightly increases the trail and helps the bike towards oversteer. With motor position, one inch further forward makes a lot of difference. As you accelerate, you tend to lift the motor and as the angle on the steering heard changes, the bike tends to self-steer. If it happens too quickly, it will destroy your confidence. The other thing about trail, it it affects the angle of lean. My bike stays more vertical than others so I can accelerate harder coming out of corners. The springs on the rear shocks affect the way the bike steers on the throttle.
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When I was racing many years ago, I knew nothing about trail or weight bias. But I found with my short stroke 500cc Triton I could not get decent lap times until I moved the motor forward as far as possible, and fitted a 2 into 1 exhaust system. The motor was too savage to have the front go light in the middle of a corner. My mate's 650 Triton was faster down the straights but slower in corners. I once rode his bike - faster than he ever could. When I fitted 18 inch wheels I stuffed the handling of my bike. But with his bike when fitted with 18inch wheels was neutral handling. The motor was that inch further back. - I never discussed the position of the motor with my mate, I only ever lowered the gearing on my bike once and left him for dead, It was dangerous to ride it low geared. I came into corners too fast behind other bikes.
 
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Schwany said:
1:39 sounds about like my little 750. lol

What cam is in that motor? Lumpy idle. I like
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Its a JS3 for BSA lifters ground to a 7/8" radius. Similar profile to the Sifton 460 and D+ cam but with improved ramps to avoid valve float.
New monoshock space frame
 
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