I would say most all the 686's running around are on stock rod's. I would think if you take care of your bike, run the right fuel, keep your jetting pretty well correct, the stock rod would hold up. It's interesting that even the Sparks bikes are running on stock rod's. Makes me feel alittle better.

 

I think I would deffinately go with a ross piston just to be safe..........and then I would feel better about running the stock rod..........
but it all depends on what YOU are going to feel comfortable with.......

 

Talking stock rods; one thing you can do to help disribute the stress put on the rod more equally is to deburr it. when you have rough spots on the rod more stress is caught on those spots; if you smooth the burrs out it helps ditribute the stress more on the entire rod maybe giving it a longer life. Slim

 

so i hear your sending somthing in to bob when you tear down a motor and send it in what do you send in? the whole motor? also in the end how much do you think its going to cost you?
-Matt-

 

It just depends on what you're doing and how much you are going to do yourself.

I will be doing a rod and the crank needs to be balanced so that is low end of the engine, since I have the 01' tranny, I might as well upgrade while I'm in there.

The first kit all I sent off was the cylinder and head, and I installed everything.

This time I will probably be sending everything to Bob for him to assemble, I don't really have the time for it right now so I will looking at more labor charges. So basically the whole engine is going to Bob.

 

I'm going send him the top end of the motor. I'm pretty sure it's going to cost me right at $1700. I have heard that Craycraft is getting some Ross piston's. I haven't found out for sure, but if they do indeed have them I will go with the Ross Piston.

And I don't think my rod should have any stress marks or burrs on it. I have not been rough on this motor at all, but I will know when I get it taken apart in a few weeks.

Anyone else with idea's or opinion's, please share.

 

Or you just go buy a yfz450 and be just as fast.[img]i/expressions/face-icon-small-wink.gif[/img]

 

I already run side by side with piped YFZ's. So I'm pretty sure $1700 in motor work will get me past them. Not to mention the video's around here show that the 686/690's are very quick. So no need for a YFZ when I can get a 686 and beat the pants off them.

But anyone else got any advice??

 

My advice would be to wait untill you can save another couple hundred and get an aftermarket rod put in. You can use RaptorTranny.com to learn how to do all of the tear down and assembly of the bottom end yourself (don't worry its easier than it sounds).
I worry about my rod everytime I ride. It was not a good choice on my part to not upgrade when I replaced my tranny, but I just couldn't wait to spend the money I had in my pocket.

 

I finally got to talk to Bob, and I'm going to change the rod.

I'll have a Full 686, with a Ross piston. Shipping the top end to Bob this Monday, or next at the latest. Hopefully it's going to be a screamer. [img]i/expressions/face-icon-small-smile.gif[/img]