how too check for a bent crank rod yz426f

i have the top end and cyilinder off. i broke a valve and have pictures of the valves and cyilinder in another post on here but nobody has responded yet. its my first time tearing apart an engine so your help is greatly appreciated.

well i see you have made 22 posts, you need to delete all but this one

1 do you have a manual for this bike?

2 as far as the crank and rod go i would have a bike shop inspect it; do you have it out of the case?

no not yet

my shop said i need about 2600 in parts does that sound right. i need a new head ,valves, cam assemnly i think , cam cainn, crank assembly, and piston and rings

The head is repairable. http://www.enginedynamics.com/

The crank has to be removed in order to correctly inspect the rod.

if the rod is bent do i need an all new crank assembly

that would probly be the best idea, that is how i would do it.

how much would it cost to repair the head i found a new one for 750 bucks at mrcycles.com

Contact Engine Dynamics and ask my guess is about half the cost of new.

Normally, by the time you pay for the labor of having the crank rebuilt, a new one is about the same cost or less.

i was planing on rebuildig the crank myself. if i send the head cyilinder to get fixed does the other cyilinder have to be bored out bigger then and get a bigger piston as well

i was planing on rebuildig the crank myself.
So, you were either going to buy the fixtures for your 40 ton hydraulic press or make them? How do you intend to align the crank after you press it together?

are you saying i need a 40 ton press to repair my crank. im not sure how to allign the crank how would you do it.

Yes, that's what I'm saying. Crank alignment requires two dial gauges, and a ball bearing truing stand just to check it. Correcting misalignments is work for a skilled, experienced machinist only.

have you done it before. i just got a crank splitter, and crank installer, your saying i would need those tools also to install a new crank asembly.

if i get the dial gauges and stand it says you need in the manual would i be able to install a new crank then or do i just need this tool to repair a bad crank.

There's no sense in checking your old connecting rod.....by the time you're in there you might as well replace it....it probably needs it, by looking at the blow-by on your piston.

You shouldn't need any special tools to replace the crank assy. with a new one (your best choice).

Rebuilding the crank is a whole different story....you'll need a rod, bearing, pin, etc and bring it to someone who specializes in rebuilding and truing them.

will i just need the crank assembley or will i need other parts in the crank.

when i buy valves do i need all of the like 20 pad adjustings. also my head top reuseable possibly it would say some money.

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