Has anyone in here ever tried a stroker crank for an lt80? Im going to give it a whirl here soon. My sons 80 finally pooped out here with the last round of porting in the cylinder. I thought, this time around, Im going to make this thing sing. Ill split the cases and see what length we can go. Ill have to make my own rod with knife edges. So, I was wondering, has anyone givin this a go yet, and if there is anything I should keep in mind?

Gary

 

Things to keep in mind hu? Well for starters, I would suppose that you would have to have the crank welded up and then turned back down. Unless you have the equipment to do this, take it to someone with a very good reputation for this. By the way, this will cost alot of money!! Next you will have to watch the piston positions as it moves up and down in the cyclinder. In 2 strokes, this is where the timing comes into play. I have no idea how to figure all that out to make it run as good or better than stock but I;m sure theres people out there that can help you. Also remeber that you'll have to get a custom piston made. (another iteam that can be very costly) Make sure you check piston to deck clearance. You don't want to have that custom made piston hit the head a gernade before it evens starts. I geuss if your making a new rod, then you could use the stock piston. Just watch the timing of everything.

 

2mm stroke. around 500.00. case work crank work and stroker plate

 

seems like a lot of money on something they out grow so fast we us the 80 for bathroom runs now. but we have found a new form of racing adults on the mini's

 

Thanks for the replies,

I own a CNC machine shop, so the work is not a problem. The only cost I will be the gaskets to put it back together. I realize the kids will outgrow the quad, but my son will be on it all next year. I wouldnt be doing this if he wasnt.

Gary

 

oh that makes a lot of difference, i thought you would be into it a 1000 bucks

 

it shouldnt be that expensive it you have materials and a cnc shop [img]i/expressions/face-icon-small-smile.gif[/img]

 

Strokers have been tried. I have one sitting in the drawer. [img]i/expressions/face-icon-small-smile.gif[/img]
This weekend we raced against against a VERY reputable LT80 motor builders stroker. The speed down the straights was the same. My 82cc motor (+.05 over)was in front of it.The stroker was under a more expierienced and older rider. My rider has been to 2 TT's and is 8 years old. So I'm not convinced that it's worth it.
FYI::For 2mm, there is no case work in volved, it clears.
Try it! Nothing ventured nothing gained. [img]i/expressions/face-icon-small-smile.gif[/img]
Why would you have to make your own rod (rod length don't make the stroke different)? The position on the crank halves is whats changed.

 

Lt80,

There are 2 reasons for the possible new rod. First being, Im not sure how much stroke I can increase it until I get into the cases. 2mm is not worth the effort. It will probably be 6 mm minimum. With that size stroker kit, I will need to add to the length of the rod also, since the cases wont allow enough clearance. 2nd reason, I want to add the knife design to the rod. This has been proven on tons of adult quads to be more effecient, so I want to try it out on this mini. The stock rod doesnt allow for that feature without drastically weakening the rod.

If you were racing someone with a 2mm stroker kit in the 80, there probably shouldnt have been that much difference in speed. JMO.

I just picked up the new cylinder, it should be here by the weekend. I will get rolling on this project once it gets here. I have a couple of ideas with the porting I would like to try.

Gary

 

I don't know how much the other machine was stroked. He said he noiticed a difference with it.
How are you going to raise the cylinder up that much? Make a plate?