crankshaft jig tool thingy

the thing you use to keep the crank true when you reassemble cases looks very easy to make. instead of paying the $100 for this thing: http://www.pitposse.com/crinjigto.html

you guys think this would work ok?

jigtool-1.jpg

Yes it would work. I use to use 2 sets of small wedges I made, 1 set on each side of the rod with the rod at bottom dead center and the wedges on both sides at TDC. The tool I have was given to me or I would still be using the wedges. They are fork shaped so it is on both sides of the rod for even support. Good luck Sean, Im sure you can make something that will work.

Ed

hi_im_sean, are you wanting one to keep, or just for one time use?

I have the OEM tool. I don't think it would be too easy to make, but not impossible.

I use a wrench. If one of your wrenches don't exactly fit you can use a thick paper shim.

CrankWrench002.jpg

CrankWrench003.jpg

a wrench? thats a relief, i was curious how accurate these need to be, obviously not that accurate. kdx i was going to made one to keep, but i probably wouldnt use it again for 5 years or something, you never know. thanks guys.

The wrench should fit like a feeler guage with a little drag. The slight angle in the open-end part allows you to bring the wrench up near the connecting rod for easy case assembly.

Like the chain breaker, I'm not a fan of single purpose tools. lol

If you bake your cases and freeze the crank then you dont need any tools. The thing will simply slide together.

If you bake your cases and freeze the crank then you dont need any tools. The thing will simply slide together.

im not taking that chance, i was going to do that in addition

I put a wrench in mine when I put them back together. I also froze the crank overnight and heated the cases to 220. The thing slid together like butter. The wrench was probably unnecessary, but it's good insurance for sure.

I surface ground two pieces of key stock and placed at either side of the rod. Thats when i noticed the the two internial surfaces of the crank are not flat or parrallel ! ! ! this was quite suprising to me.

a wrench? thats a relief, i was curious how accurate these need to be, obviously not that accurate. kdx i was going to made one to keep, but i probably wouldnt use it again for 5 years or something, you never know. thanks guys.

I wouldn't be relieved that using a wrench would indicate that its not that critical, and if you don't care how smooth your motor is or long long it will last, then your right it's not that critical. However, if you want you motor to run buttery smooth, perform to it's max potential and last for a long time, then it is critical. Granted you will probably never get to 0 but not unheard of top get to half a thousanth if your paitent. If you do your bike will run so smooth and perform better than it ever has. I might take some short cuts on some things, but never the crank, when my kid raced 80's you could tell a true crank from on that wasn't, and after the first I never lost another crank, its the heart and sole of your bike, make it right and you'll be happy.

Sorry jeekinz but I'm not feeling the wrench, right tool for the right job.

And as somebody else said heat and cold are your friends, not sure about the bake job, but I guess it could work, remember you have rubber seals installed before the bearings so don't get to hot.

I wouldn't be relieved that using a wrench would indicate that its not that critical, and if you don't care how smooth your motor is or long long it will last, then your right it's not that critical. However, if you want you motor to run buttery smooth, perform to it's max potential and last for a long time, then it is critical. Granted you will probably never get to 0 but not unheard of top get to half a thousanth if your paitent. If you do your bike will run so smooth and perform better than it ever has. I might take some short cuts on some things, but never the crank, when my kid raced 80's you could tell a true crank from on that wasn't, and after the first I never lost another crank, its the heart and sole of your bike, make it right and you'll be happy.

Sorry jeekinz but I'm not feeling the wrench, right tool for the right job.

And as somebody else said heat and cold are your friends, not sure about the bake job, but I guess it could work, remember you have rubber seals installed before the bearings so don't get to hot.

:worthy:

I wouldn't be relieved that using a wrench would indicate that its not that critical, and if you don't care how smooth your motor is or long long it will last, then your right it's not that critical. However, if you want you motor to run buttery smooth, perform to it's max potential and last for a long time, then it is critical. Granted you will probably never get to 0 but not unheard of top get to half a thousanth if your paitent. If you do your bike will run so smooth and perform better than it ever has. I might take some short cuts on some things, but never the crank, when my kid raced 80's you could tell a true crank from on that wasn't, and after the first I never lost another crank, its the heart and sole of your bike, make it right and you'll be happy.

Sorry jeekinz but I'm not feeling the wrench, right tool for the right job.

And as somebody else said heat and cold are your friends, not sure about the bake job, but I guess it could work, remember you have rubber seals installed before the bearings so don't get to hot.

i completely agree, i know the seals have a temp limit, and i have considered that. i baked em at 200 F to get it apart and it seemed to have no visual effect on the seals. i always use temp differnces when i assemble interference fit componants, it just makes life easier and gives me peice of mind that i didnt damage a bearing by pressing to hard.

thanks for everyones input

The OEM tool allows the bearing to be at the bottom, while the tool supports it at the top.

In the late 70's KX / KDX manuals, before the new tool was available, they show a chisel being used as a wedge.

Yes it would work. I use to use 2 sets of small wedges I made, 1 set on each side of the rod with the rod at bottom dead center and the wedges on both sides at TDC. The tool I have was given to me or I would still be using the wedges. They are fork shaped so it is on both sides of the rod for even support. Good luck Sean, Im sure you can make something that will work.

Ed

are those goats in your avatar?

Now now, you know those are two of my dogs and Clyde is the one on the left. It was fun riding with you last week.

Ed

Seals hold up well beyond 200 f - they get way hotter than that every time you run your bike!

I also use a wrench as stated, cranks pins are in so tight it takes a LOT of force to dislodge one - chances are pretty slim you'd knock your crank out of true while tapping cases in place, you'd probably have to crack a case before knocking a crank out of true.

Seals hold up well beyond 200 f - they get way hotter than that every time you run your bike!

I also use a wrench as stated, cranks pins are in so tight it takes a LOT of force to dislodge one - chances are pretty slim you'd knock your crank out of true while tapping cases in place, you'd probably have to crack a case before knocking a crank out of true.

top end seals get above 200, sure, but i doubt the cranks seals do, id guess they run right around 200. but i agree, im sure they can handle a good amount of heat

right where the seal contacts the shaft and the shaft spins at 12000 rpm.....what kind of heat do you think is present there......

the heat from the top end migrates to the bottom end over time - if you run the bike for 2 hours non stop, the bottom end will probably be within a few degrees of the top end. If you run motos and it cools in between - probably like you said - not so much, but go for a nice road trip/trail ride.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now