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Discussion Starter #1
Hey does anybody know what size and pitch the threads are that are in the crank that the bolt holds the clutch on is? The motor is a 87 Indy 600. I was told they were M11 * 1.25. Is this correct? I am having a heck of a time finding a tap this size. Just the first 2 or 3 threads are messed up. Any help would greatly be appreciated.
Thanks Everybody

:doh: SWRules
 

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I do not know the size right off hand. If you cannot find out, I will on Monday. I can tell a short story about clutch threads.
I am not a trail rider, but some friends convinced me to go on a ride to a lodge and spend the weekend. I had just finished a rebuild from a minor incident with the crank, the week before, but was confident that everything was alright. We hadn't gone 20 miles , when we were crossing a wide lake, we opened them up a little. I started feeling an all to familiar vibration, CRANK, let off the throttle just in time to here a horrible noise under the hood and then saw stuff spitting out the side of the tub. OH CRAP! We are in the middle of nowhere, I mean interior Alaska, nearest parts are 150 miles, mostly thru woods.
Jumped off and opened up the hood, Dam clutch is laying in the tub. Bolt, washers and the bushing are gone along with the rubber plug in the tub. There was a large group of us riding together, but odds were very remote that anyone had these items. Started back tracking, about a foot of powder on top of ice, oh cool, there's my plug. Kept looking, saw a dimple in the snow, about 25 yards from my sled, stuck my hand down in there, AAAAH, the bolt. Still missing the bushing and the spacers(washers), kept searching and searching, I found every piece that spit out. UNBELIEVABLe.
Started trying to assemble it back on crank, the threads are boogered up, even when I can get a little bite, there is no way to keep the motor from turning over when the threads start crossing. Oh man its going to be a long pull back to the truck. One of my friends rides up and says, "hey, why don't you dead head it" hunnh. Rabbit (my friend) says here let me show you. Gathers up some rope, takes the plugs out, feeds some rope down the cylinder, turns the crank till the motor locks up. Now all we have to do is get the bolt started straight. Rabbit says anybody got any grease. Dam, none anywhere, not even on the skid from greasing it, then Linda says," I don't have any grease, but this Chap Stick looks like grease". What the heck, give it up. Chap Sticked up the threads on the bolt, Rabbit started threading it in and out real gentle like until all of a sudden it freed right up. Torqued the bolt down to 50 pounds and rode the rest of the weekend.
So if you can't find a tap, Chap Stick that bolt and re thread it. LOL
 

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and that my friends is a story that i am glad is not mine. :thumbsup:
 

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Proof positive that those alaskans are a breed apart from the rest!! :D

A McGuyver move if I have ever hear of one, plus there is a guy named Rabbit in the story!
 

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That dead head thing sounds alright, :p Ill have to remember that little trick. ;) ya know,just in case,and its true,(especially 150 mi.from parts!)necessity is a mother,of invention! SWRules
 

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Discussion Starter #10
Omotm that is one crazy storey. I could never have that luck. If you can, I still need to know what the threads are. It would be a great help. SWRules
I need to get this thing together. It has been one long summer project :cussing:
 

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If they are a M11x1.25 that would be an uncommon thread size,but not unlikley for them to use something like that. The more common size thread would be a M12x1.25. If you are measuring the shaft where the threads are remember the major diameter would measure just under the nominal size of the thread. Ex. 12mm= .472"=max.major diameter.The major dia. for a 1.25 pitch would probably be something like.460-.465" . The minor diameter (hole size) would probably measure something like .423"(12-1.25=10.75mm) 10.75/25.4=.423" give or take a few thousands. For an american size 7/16-14 ( 7/16=.4375 ) ( 11MM=.433) would be the common, but seeing the motor is a Fuji Industries made in Japan they would use a metric thread. If you don't have a micrometer or a set of veriniers I would take the shaft to your local hardware store they should have a bolt gage that will measure the "major diameter" then you could take a bolt with the same thread pitch ( 1.25) and match it to the pitch of the thread on the shaft. In the 14 years I have been a machinist I have never run accross an M 11 thread, but that does not mean it does not exist. M12 is the common size. Sorry for the long post, but I hope it helps. Good luck. If you do find the right thread get a plug or starter tap they have a chamfer on them to hook in to the good threads behind the mashed threads a bottom tap has a short chamfer which might not hook in to the good ones.
 

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Discussion Starter #12
Yotaholic It is a very uncommon thread size. The machine shop that i went to didnt have the tap. The kid there tried to put the bolt in a 12*1.25 die or nut, not sure. He said that the bolt went in but it was sloppy in the nut. One other person tried to get the thread type for me off the bolt and they too said 11*1.25. She couldnt even order the tap for me. I know where there is one, but I wanted to check and make sure they where correct. It seemed odd that they would use such an odd size. But like you said, MADE IN JAPAN. So who knows. :doh: SWRules
I am going to my dealer tommorow night, see what they have to say or know.
Thanks
 

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Try a 7/16 - 20 (UNF) tap. It worked for me.
The metric 11 x 1.25 is not a standard thread.
but ... 7/16" = 0.437" = 11.1 mm
and 20 tpi = 0.05" pitch = 1.27 mm pitch
 

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Discussion Starter #14
Thanks Need2Snow. Welcome aboard!! I know where i can get the 11 * 1.25 tap but wasnt sure that it was it or not!! I too need some snow!! SWRules
 
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