dajogejr

Always one of the first things I do... Any hardware store should have metric stainless and possibly chrome as well. Ace does have a nice assortment. I can't stand the phillips screw heads on them. With a hex/allen head, you just snug 'em down with a T handle and be done.

I'm gonna put my 2 cents in...even though I know this is not a plated vs. cast iron discussion. AK... I've smoked two pistons in 5 years on my current 10 mil cub. After 4 seasons of a TON of passes, it was finally time to replate my cylinder. I just smoked another piston...and the plating is fine. Your argument could go both ways. If you smoke a piston with plating, most of the time you run a hone through it and throw a new slug in, no down time. If you blow a piston with cast iron, you remove it...bore it, hone it...get a larger piston for BOTH sides...etc. I agree, IF the plating goes, it's expensive. Plating is around 250 give or take. Bore job and new pistons are about the same...

Andy, Great, Great response. This is absolutely critical to read over and over....and why it's important to buy things off folks who race and use what they sell. That ebay price might look great...but you're not getting the research and service. I would agree 100% to true and weld these in house...just to be sure. Nice write up Andy... Folks, how many other people took the time to send connecting rods out to a metallurgist for R&D to give their customers the best option...

My Pleasure Cody...glad you're still enjoying it and it's working well for you!

That's what I was wanting to know...or hoping should I say. Thanks!!!

Jeffro.... Details on the cylinder head being used for the 72mm bore?

I agree...don't waste your time or money on an override (dunable) for trails. Get a tranny with every other dog cut off and get the shift pro kit.

You'll get 10 different answers on this one...my advice is get one from a builder that races with what he sells, trues and welds it himself before sending it out.

That's the only good reason I could see doing it. You won't notice any more power 4 to 7, even if you take the time to match/fix the porting. Obviously you'll have to run a spacer plate or cut domes.... Extra cranks is the only reason I'd see running one. You won't notice a performance gain...and if so it'd be so minimal the cost wouldn't be worth it.

Why build a 7mm out of a 4mm cylinder?

Did he buy the cheap crank or the more expensive crank from TDR? Over on ATVDragracers.com, this is a DIRECT QUOTE from Tony Dukas himself. Hey Guys. The crank parts are imported and them assembled in the US. All the components are Taiwan made and seem to be holding up fairly well so far. If you are an abusive rider, over-rev especially I would always suggest the better crankshaft. We are stocking them to be able to be competitive with all the other vendors. We still have all the higher quality cranks and parts in stock as well. I have also been updating my website daily with a lot of new items. If you have more questions on the cranks or any parts just contact me. Thanks Guys Tony Doukas

TDR has a cheap and expensive 10 mil. The cheaper one looks like the one everyone is carrying, and it's CHEAP...less than 500 for a 10 mil crank. The other, which I think is like 800...is what looks to be a crank works crank.

My strong advice is to get a matched set of cases, upper and lower...or you could be repeating the problem. They're machined as a set....and you've had enough issues that I'd want to eliminate as much as possible before firing the motor. I live within 45 minutes of Vitos. I had three cranks delivered to my buddies house. none of the three crank's welds look like the one in your pictures. They all look clean and nicely done. Are you/your buddies buying them direct from Vitos?

Welds look like shit, cases are hit...flywheel post is all fucked up... Crank aint' the problem, although it might be fubar now. Jared, PS is down right now or I'd get you a picture of one of our friends 10 mil cranks that snapped off at the web. And that happened to two of our friends. They put forged in and no problems since. New cases for sure, don't send that crank back to whomever welded it...I don't care if it was Vitos or not, and get a TZ bearing as said for the PTO side. You might as well get straight cuts with all the problems you're having. Personally, I ran my 10 mil for 3 seasons and LOTS of passes without straight cuts on my TZ. Maybe I just got lucky....but I certainly didn't have the problems you're having.

The three I've seen at my bro's house were within .002. They were true. They were also welded sufficiently... However, I run my shit hard and I replaced the stock bearing with a TZ...so welding it all the way around was no big deal. Stroker has had all these cranks fail...by separating. In my opinion the factory welds on them are sufficient...and also in my opinion there is something else wrong with the motor and/or it's state of tune if it keeps happening. Once on the same crank, maybe. More than that and on other cranks in other motors...I'm doubtful/skeptical at best. The other cranks, in motors other than mine, are still running, running strong and trouble free. One in a twister the other in a K&T ported 10 mil cub. Tyler, if he puts a crankworks crank in there and the same thing happens, you gonna come back here and say Vitos aren't junk? (I already know the answer to that question...because you had them go bad on you...you're not) My point...is the problem lies somewhere else. Stroker, do you have an old or lightened flywheel by any chance? What kind of bearings? What kind and how old of a clutch basket? (Please don't take any of this personal, I'm just trying to figure out the answer...I also have a Vito's crank as said...and it's fine)

Stroker, when you pull these out...take a picture of the side of both webs. I want to see where it's welded, please.

Stroking, when you put another crank in your bike and don't change anything else, I'd give that statement some weight... I have one, no issues like this. Although to be fair, I didn't ride this year very much. I hope that changes next year.....

That's too bad... I bought my crankworks crank used off ebay, put a TZ on it and ran it for three seasons, thousands of passes...nadda. No issues. I almost put another TZ on it and ran it again but I felt it deserved to retire with what I put it through..... I've seen more billet cranks break than forged around here, and we have a lot of 10 mils.

Hate tell tell ya Tyler, but if Vito's sells junk, everyone does.... They're all made in Taiwan with different people badging their names on them.

Should never happen.... Are you guys rewelding them? Have you tried different flywheels? What kind of bearings are on them? I can see if they explode, but if they keep separating like that, different cranks no less, there is another problem. Yes, flywheel and too much over rev could certainly cause that.... I only put 40 to 50 passes on my bike this year...I have my buddy weld all the way around the pin, and no issues like that. Try another brand crank, but I have a feeling you'll be seeing the same thing again...

Please don't take this as me being a smart ass... If you put a different brand crank in the same set of cases with the same setup and it doesn't fail, I will 100% support you in saying the cranks you got from Vitos are junk. Until then, I'm convinced it is something else...and any of the cranks coming out of Taiwan would have the same issue.

Not trying to steal Jeff's thunder, but they don't offer this cylinder cast for a 7mm crank, at this time it's stock stroke and 4mm only. That being said, that's up to Jeffro if he/you wanted to port the 4mm version to work with the 7 mil.

Unless your crank is made of butter, there is an issue somewhere else. I've seen more billets break than forged, and there's a LOT more forged out there. If they are separating after being welded...either the welder isn't doing the job correctly, or there is a MUCH bigger problem in the motor, it's mating/bearing surfaces, something out of balance/true, etc. Now a days, all the cranks come from pretty much the same place, just different names on the box. A 120 rod is not as common for the 10 mil. There are a few 10 mil cubs with that rod, I'm not sure about the twister, and the super cubs (72mm bore) might use it. The 120 rod is available in a big pin or small pin. If it's the small pin, no extra trenching is required. The big pin has a larger bearing so that's why it needs to be trenched a hair deeper. That being said, Vito's doesn't offer the 120mm rod that I saw... I have a Vito's 10 mil in mine. It's a quality piece. I watched my buddy unbox 4 of them, NONE of them needed to be trued. He just welds all the way around the pin. I also like their new cub pistons.... While I don't agree with some of their marketing hype...I do think their products now a days are quality. Separating a crank 3 times...it's possible you got a bad one, but I'd be looking else where to be honest.

Depends on how thick the sleeve is in them. Also depends on piston availability...you're going to have to figure out what kind of piston you're gonna use for that size. I believe CT racing is still around. They built pretty good stuff back in the day... http://www.ctracing.com/

Great pricing Jeffro... I'm really pondering building a duner with one of these slapped together. Question...12 pt. ARP nuts. Are these the stainless or black oxide? I'm looking to get some for mine and I already need a clutch from you for next year and some other parts as well...