Hey fellas , gotta rebuild the 650 , took the crank out of it.I'm wondering if anyone has put the 700 crank and rods in the 650.I heard that it is a viable option.I'm getting the crank spray welded and turned to fix it.My machinist tells me that adding the extra stroke won't cost any more.

If its only gonna cost me a set of rods, I figure I'm gonna do it.I only want to make sure that the difference is in the rods and not the deck height on the pistons.

I also plan to install an offset flywheel key, Mbrp slip-on and I already have the DG snorkel and EPI black spring.I intend to rejet as well.
I'd like to hear from anybody with any advice on the topic, also any good ideas on makin' more ponies while I'm already there are appreciated.

 

Mickey Dunlap's Four Strokes Technology has a wonderful 750 Big Bore kit for the Prairie 650 and 785 for the Prairie 700. It is very reliable. And many on this forum have performed the mod. I am planning on it. And don't forget to buy a holeshot or High Lifters electronic module to unleash all that extra bottom end power!

 

I'd love to do that, but $ is the common denominator,My machinist can fix my crank for a couple hundred bucks, my top end is ok.It was smokin' bad and the dealer bored it 1 size over under the warranty for me, 300 km later, took it in for knocking noise, they found the crank bad, warranty not gonna cover this, so its up to me.Long story short,,,,,I only need to rebuild bottom end.

I live in Canada so anything from the the states doubles in price at the border when you convert to canuckbucks.I'm guessing aroound 3000 for a big bore kit up here.

Anyhow,, I figure I could probly scrounge up the extra 200 for a set of 700 rods,,, the crank won't cost any more than to go stock and a flywheel key is a cheap mod.Also, I think I can get a key at Dalton Industries, and they are a 15 minute drive away from my house

Don't get me wrong, I'd love a 750 kit, but the added expense of the divorce would finish me off............[img]i/expressions/face-icon-small-wink.gif[/img]

 

KM you need to tale to mike he said that the rod are longer . So the deck heigt should be the same. You will also have to buy the timming shaft, two new pistons, rings, etc. All this is going to be around 1k minus the price of the crank. I'am not sure about the big bore kits price but i think i would go with it cause you getting 50 more cc's.

 

The FST Big Bore kit goes for 1040 US$ so that is 1400 CAN$ with shipping. I also come from Canada and right now the money exchange is at its best. At the Kawasaki Dealer, all the parts it would of took to make Prairie 700 conversion would of cost me more than 2000 CAN$. FST's phone number (814)842-6159.

 

You need to find out if the 700 has the same length rod as the 650. If it does. the piston will have to be changed, also, because of the location of the piston pin hole. I am guessing that the piston has to be replaced with the swap.

 

You would need 700 crank, rods, and taller cylinders walls. Mickeys kits are now larger than 750cc.

 

Getting a little confused, now. Real question is:are the 700 rods longer?If so,, how much?I'm not really trying to build a 700.My current top end is fine.Just gotta fix the crank.I CAN , however, add the extra cc's of a 700 stroke by just replacing the rods if deck height is the same for 700 and 650 cyls.Probly only works out to 650 cc's total, but won't really cost much more than going stock sizes.



Littleboy,, that doesn't sound as bad as I was imagining, what does the FST kit include?Do you have to trade in the old parts?

 

The FST kit includes everything new cylinder sleeves, forged wiseco pistons, rings, pins, high performance camshafts, gaskets, heavy duty valve springs, and all the little parts needed to assemble this thing together. It's complete. You only have to give your camshafts in exchange. I have only had positive comments of this big bore kit.

 

The 700 rods should be shorter than the 650 rods. If they aren't, then the piston pin holes would need to be lower in the pistons, which would mean that you couldn't use your old pistons.