How do I weld motor mount?

There's no power running through the return side of the chain where the rear derailleur operates. Therefore I *expect* that even on MBs the failings of the derailleur systems are down to improper installation and maintenance, ie choosing cheap derailleurs (check the reviews on the ebike/MTB/etc forums), "chain suck" from worn chain and/or sprockets (you should expect to replace them very frequently), and overenthusiastic operation of the throttle. Impossible to prove that, though. I am going to try anyway (with a 66).
But one thing is certain, a narrow ie multi speed chain concentrates wear. Halve the chain's internal width and you halve it's lifetime. This may be acceptable for a relatively pathetic 66cc but maybe not with a 125cc that outputs a lot more than double the HP.
Is my thinking.

Is a dingle acceptable? Two single speed ratios, using the same total tooth count (for the same chain length) on two different lines, both lined up correctly, but you have to stop, release chain tension and move the chain manually between the high speed sprockets and the town/hills sprockets. It is (not popular but known) from fixie cycling.
I have been looking at it for the 66 but the sprocket cover /clutch lever mount dimensions cause real issues and limit the possible ratios and would require significant modifications. This may not be such a problem with the engine you're looking at. idk how the output sprocket looks on those but I think it would be worth checking out.
 
There's no power running through the return side of the chain where the rear derailleur operates. Therefore I *expect* that even on MBs the failings of the derailleur systems are down to improper installation and maintenance, ie choosing cheap derailleurs (check the reviews on the ebike/MTB/etc forums), "chain suck" from worn chain and/or sprockets (you should expect to replace them very frequently), and overenthusiastic operation of the throttle. Impossible to prove that, though. I am going to try anyway (with a 66).
But one thing is certain, a narrow ie multi speed chain concentrates wear. Halve the chain's internal width and you halve it's lifetime. This may be acceptable for a relatively pathetic 66cc but maybe not with a 125cc that outputs a lot more than double the HP.
Is my thinking.

Is a dingle acceptable? Two single speed ratios, using the same total tooth count (for the same chain length) on two different lines, both lined up correctly, but you have to stop, release chain tension and move the chain manually between the high speed sprockets and the town/hills sprockets. It is (not popular but known) from fixie cycling.
I have been looking at it for the 66 but the sprocket cover /clutch lever mount dimensions cause real issues and limit the possible ratios and would require significant modifications. This may not be such a problem with the engine you're looking at. idk how the output sprocket looks on those but I think it would be worth checking out.
Actually his kit has an internal 4 speed transmission, I wouldn't even bother jackshafting it with that, it's almost like the single speed of a 2 smoke but you have the ability to shift at will, the 4 stroke kits for bikes don't even have a manual clutch or transmission, you have to let the machine do it for you.

The reason I suggested the nuvinci is the hub is a single speed gear, you could put a pretty thick gear on it too and with some very heavy single speed chains too, that virtually eliminates chain problems. (I use a nuvinci hub, and kmc half link chains, they are tough nuts too, of all my issues I had I never had chain problems after upgraded to it, been using the same chains for 8 months now with very minimal stretch or wear to either the chain or sprockets. The only thing that went bad was my left side jackshaft sprocket, the big one, it got eaten up.)
 
Actually his kit has an internal 4 speed transmission, I wouldn't even bother jackshafting it with that, it's almost like the single speed of a 2 smoke but you have the ability to shift at will, the 4 stroke kits for bikes don't even have a manual clutch or transmission, you have to let the machine do it for you.

The reason I suggested the nuvinci is the hub is a single speed gear, you could put a pretty thick gear on it too and with some very heavy single speed chains too, that virtually eliminates chain problems. (I use a nuvinci hub, and kmc half link chains, they are tough nuts too, of all my issues I had I never had chain problems after upgraded to it, been using the same chains for 8 months now with very minimal stretch or wear to either the chain or sprockets. The only thing that went bad was my left side jackshaft sprocket, the big one, it got eaten up.)
Totally agree, four speeds is probably fine, four times seven is unnecessary and expensive. I only mentioned the dingle system as an idea that needs no jackshaft or quite so narrow chain, BUT now I think it could never have a big enough difference in the ratios to matter when the engine already has four gears that have a decent range of ratios. The new speeds would just be in between the old ones.
I can't really comment on nuvinci hibs, but I have read about differing experiences. I don't like that it is a disaster if I does break down away from home.
So what are you using for the left hand JS chain? How often do you check length and replace the chain? Is the sprocket the steel SBP one or the alloy?
 
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Totally agree, four speeds is probably fine, four times seven is unnecessary and expensive. I only mentioned the dingle system as an idea that needs no jackshaft or quite so narrow chain, BUT now I think it could never have a big enough difference in the ratios to matter when the engine already has four gears that have a decent range of ratios. The new speeds would just be in between the old ones.

It's also a 4 stroke, the powerband is nicely spread across most of the rpm range, that means, unlike a 2 smoke, that for the most part you'll be getting good power on the gears, and the powerband can overlap them rather nicely, I guess at that point you just gear the rear wheel for a modest mix of speed and climbing ability at the high and low end gearing.
 
I also think that battery and light system is pretty cool too, I might end up ripping my setup off and putting that fancy one in, it's just the battery maintenance that I hate... Course with my set up I usually pull the battery in my bike, put it on the charger and put the charged one in, it's super easy but I want it to be easier.
 
I also think that battery and light system is pretty cool too, I might end up ripping my setup off and putting that fancy one in, it's just the battery maintenance that I hate... Course with my set up I usually pull the battery in my bike, put it on the charger and put the charged one in, it's super easy but I want it to be easier.

They sell the same kit with a 2 stroke charging system but its more expensive
 
So the other thing i take from this is that the jackshaft would be useless. If thats the case where can i find a 4 stroke Jackshaft mounting braket

Screenshot_20160811-205147.png


Essentially it's basically just going to be used to support the bottom of the engine and this mount would be mounted to frame like its ment to be and then weld it on there
 
So the other thing i take from this is that the jackshaft would be useless. If thats the case where can i find a 4 stroke Jackshaft mounting braket

View attachment 73333

Essentially it's basically just going to be used to support the bottom of the engine and this mount would be mounted to frame like its ment to be and then weld it on there
No idea what would fit with that engine and frame or why you would need the jackshaft mount if a jackshaft isn't to be used, but Sick Bike Parts do sell most of their shift kit parts as separate items for the custom builders.
 
So to kinda get a rough ideal hear this is kind of my plan
20160812_175732.jpg

Red is mounting plate preferably the jackshaft one.
Blue is where i plan on welding the mounting plate in position this being after i mount with steel hardware and weld it all together.
There is blue on top bar and top of engine where they use a bolt or something of that nature i plan on making some kind of welded mount that can just be unbolted
The yellow dots is the bolt hole pattern for the bottom
And green is the engine in hopefully somewhat of a good fit without having to cut parts of the frame.
I am also thinking of getting some of those side bars that go with the knee guard things on the harleys not the same thing something of similuar nature would weld some mounts on top and bottom of both sides of bike then fabe some bars to reach from top to bottom to give the bike more reinforcement as well to add a cage for engine just in case and with making a bracket to weld to the frame and bolt up easy to take apart if i ever had to remove engine

So tell me what you think so far of my plans any and all advice is welcomed
 
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