welding a crank

[sblt500r]

whats the point? i can understand it on a banshee but why on a single?

[fast350]

the more power you have, the more stress it places on certain points of the crank

[370banshee]

i dont; really uderstand it on a single either.... except a crank wouldnt; star to seperate when it got old.... and it might keep the conn rod side play in spec longer...

[369DuneBunny]

imo. . . for motorcycles. . . shouldn't you just bye a brand new crank if yer stock one or old one needs fixed? at least that's what i'd do. . .

[sblt500r]

well a set of rods and the cost to install them is usually cheaper than buying a whole new crank assembly. but on a banshee or blaster thats really not true becuase of the supply and demand.

i just got a used zilla crank that was welded. i can't see the point. has anyone ever tried to press apart a zilla crank? i had my original which i did about 8 years ago. it was set up in a 60 ton screw press. and man when that pin let go you should have heard the crack echo through out the shop. so i can't see it just happen to move by itself.

also i learned back in desiel school, that when you weld on something that has bearings in or on it that the bearings get little pit marks which in turn causes premature failure of the bearings. example welding on a snowplow with the ground on the snowplow and then go to the rear to weld something on the bumper but leaving the ground in the front, the arc goes throughout the whole chassis.

[wicked251]

I was told many years ago that the crank in the Zilla would twist over time. The guy who orginally built my engine for Ice racing welded my crank 16 years ago and I havent had any problems. I dont know if these cranks really need to be welded or not. But I have had no problems with any bearings, seals ect. Just my .02

[MWC]

again, being very new to all of this shit, what is the reason to "weld and true' your crank? And does someone have a link to some illustrations of what this is? I know, damn noobs, lol

[sblt500r]

to true a crank, you are aligning the 2 crank halfs so there in sink. if there out of wack they will vibrate. a shop ussually has a jig so when the 2 halfs are pressed together they will be aligned to with .001" and they check them between 2 V blocks and a dial indiactor. and if there out of wack they half to hit one of the halfs to get them aligned.

welding a crank is when the crank pin is welded to a crank half, which in theory stops the halfs from moving and getting out of true. which is why i started this thread because i can't see how there gonna move.

[flotek]

yamaha banshee and blaster cranks have a tendency to seperate because of a lousy desig n how theyre pin is pressed in ,the lt series arent known for that so much , but theyre bearings go out instead ...also the cases are poor quality and bearings themselves are too small for the load. hondas had a good thing going when it comes to cranks IMO .

[odaen]

people are pulling 3x the HP out of their stock stroke motors, compared to stock, running compressions and RPM's quite a bit higher too. if a crank can take that kind of abuse and demand, it must not be all that bad, even with a couple of small beads around the pins.