New year projects

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Ok , Happy New year tasks/ projects to you all.
Two years ago l bought a Laverda 750 1997 , its a wonderfull thing, or was. the bike as all the goodies , Brembos etc , anyway this came cheap , one reason was it was a buyer collect and with 6inch of snow no body bothered.
To the point ,i sold the engine for what i paid for the whole bike,so i have a super rolling frame ..free.
I have also a Norton engine looking for a home..so there i am looking at the two thinking ERRRRMMMM :roll:
First thing i see is the chain alignment being a problem , unless the engine is mounted over 25mm to the clutch side its a no go'er , would 25mm matter? Arnt Commando motors off set to start with :?:
 
Look up Daniel Delfour in your search engine. He's done it. I think he used the 650 Ghost frame, but have a look anyway. Tight fit.
 
john robert bould said:
.............First thing i see is the chain alignment being a problem , unless the engine is mounted over 25mm to the clutch side its a no go'er , would 25mm matter? Arnt Commando motors off set to start with :?:
Yes I believe the engine in a stock frame is offset, but I'm not sure by how much.
 
Average engine offset to LH is 3/16" but can vary from 1/8" to 3/8" inch and easiest to see by the offset rear rim and chain drive run.
 
John, you could first find the longitudinal balance point of the Commando engine/gearbox and cradle. It is likely not in the same exact location as the crankcase centre line. Some experimentation here is needed, but a piece of plywood placed under the cases and section of 2" pipe placed longtitudinally under the plywood worked well for finding the balance point for the engine used in my Special.
I had to shift that engine 16 mm to the right for chain alignment. It turned out that as far as overall balance was concerned, this was an improvement over the stock alignment, though 12 mm would have been ideal for perfect balance.
My point is that a stock Commando engine alignment may not be ideal for balance and by shifting alignment for the Special, you might actually improve things vs a stock bike, which is likely not perfectly balanced with the wheels vertical.

My completed project bike with the 16 mm offset vs stock goes around corners very well. I don't think a small amount of lopsidedness matters for a road bike.
I have ridden all day a few times with a full 40 pound pannier on one side and an empty 10 pounder on the other side. Even though this is a large inbalance quite far out from the tire/frame centreline, once underway, the inbalance is not a problem, in fact it isn't noticeable.

Glen
 
john robert bould said:
........I have also a Norton engine looking for a home..so there i am looking at the two..........
John is your donor engine an older 750 or an 850 with the thru bolts from the head to crank case. Might make a difference. Just a thought. Cj
 
All the Laverda bikes I looked at had the chain on the wrong side. I think you can take care of the offset in your selection of a rear wheel. Looking at the Norton Commando engine from the front of my bike the engine looks like it is in the center of the frame. Look at the down tubes and exhaust headers and head steady etc.
Dan.
 
motorson said:
All the Laverda bikes I looked at had the chain on the wrong side. I think you can take care of the offset in your selection of a rear wheel.
Dan.


I think Dan has it here John......

You may choose a cast wheel, which is probably a bit less flexible as you won't be able to play with offset, either way you will have to work brakes as well as chain run and front to rear wheel alignment. You will probably end up having to make a set of engine plates and ofering up the engine/trans and spacing the plates to the frame mounts as a first installation item.

You can get more wiggle room by choosing the lightest chain that will work with your 750, that would be 520, and spacing sprockets around as required . Get a laser tool to check chain alignment and get within 1mm.

I guess the point about the bolt through barrels is that the frame has no down tubes?

Rather than source an 850 when you have a 750 already you could budget for a pair of AN bolt through 750 barrels, or if you want to save some weight Maney barrels.

Surely you will want to tear it down and rebalance it anyway if you are not going to try and keep isos in it! But it may not really be that much of an issue, it wasn't for 750s in Seeley Mk3 frames with just those spindly front down tubes...... and I am sure some '70s race frames had no down tubes at all.
 
If the chain is wrong side then flip the wheel over to make it right for your Norton engine/gearbox. The brake stay will then likely be in compression rather than tension,(a few production bikes have stays in compression, most are in tension) so a new, stronger brake stay can be made.

Glen
 
Agree the motor needs thro bolt cylinders if it's going to be "hung" via the head, i think brent Bewolf welding looked at a modern kwak frame and had my thoughts .."where is the motor fixed?" .
 
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