Crank going bad
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If a guy wanted to have a crank plugged, trued and welded before hand, how would the best way be to go about it? While Im at it, Id like to have forged rods with the bushings for the wrist pins and I would want to keep the stock 4-3/8" stroke by the way. What options are there? Would you go back with HD components or would you go S&S or SE or ? Id like to do a build but I want everything ready to go before I start tearing it down and the crank issue seems to be my biggest hurdle. The rest is just buying the components.
It should state how to avoid engine from breaking.
If a guy wanted to have a crank plugged, trued and welded before hand, how would the best way be to go about it?
4 3/8" stroke, but you would probably want to have the true checked and have it welded. There are options.
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Stay on the throttle and never back off!!!!
You might be able to pick up a stock crank at an Indy that is out of true and has been replaced for little or nothing. You're gonna have it trued anyway. The one I go to for dyno work has two or three of them sitting on the floor. You can go with S&S, but you'll have to go to 4 1/2" stroke, makes a 106 ci. Revolution Performance can split a stock crank, put in the rods and new pin, true it, and weld it. You can buy a forged SE crank in
4 3/8" stroke, but you would probably want to have the true checked and have it welded. There are options.
You might be able to pick up a stock crank at an Indy that is out of true and has been replaced for little or nothing. You're gonna have it trued anyway. The one I go to for dyno work has two or three of them sitting on the floor. You can go with S&S, but you'll have to go to 4 1/2" stroke, makes a 106 ci. Revolution Performance can split a stock crank, put in the rods and new pin, true it, and weld it. You can buy a forged SE crank in
4 3/8" stroke, but you would probably want to have the true checked and have it welded. There are options.
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Unless I was building a real monster of a motor. Disregard what I said above, if that is the case.
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I can't answer that, but I personally wouldn't put a high priority in spending the extra money on the rods. The slip fit non welded crank is where the multitude of reported problems come from. A trued and welded stock crank would make me sleep real well at night.
Unless I was building a real monster of a motor. Disregard what I said above, if that is the case.
Unless I was building a real monster of a motor. Disregard what I said above, if that is the case.
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"Wouldn't want" ain't exactly how I'd put it.
Wouldn't brake the bank to do it. I guess I am in a conservative mode lately due to finances. That sways some of my opinions. I don't see it as a high priority item, when all the failures I see are run-out related.
This blaming the MoCo gets a little old. How many stock bikes have had crank failures? Not many. HD designes them for the bike being stock. So if they design a part to handle 70 HP and it fails on a bike making 100, how is that there fault? This is going to be a larger problem in the future, builders are figuring out how to get alot of power out of a top end build. Let this be a caution for those wanting "big" numbers from your budget top end build, the weak link will be the one that breaks. In this case it's the crank. Here's a better idea, if you don't want the money to build it right, and don't want to fix it later, then keep it stock and you won't have a problem. This problem is the same as plugging 30 appliances into 1 outlet and blaming SquareD because your breaker tripped.
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This blaming the MoCo gets a little old. How many stock bikes have had crank failures? Not many.
A friggin' misplaced downshift will throw you out. A downshift don't care how many HP you have.
Shifting a decent powered motor near the rev limit is a lot safer that a poorly placed downshift on a stock motor.
Shifting early on a built motor ain't no good for the crank. Ruined one that way myself. The gear ratio's are where they are supposed to be if you shift near the top.
keep it stock and you won't have a problem
This blaming the MoCo gets a little old.
Edit: I gotta add, I'm just debating with you and still have a high opinion of you.
Last edited by Faast Ed; Mar 21, 2011 at 05:04 PM.
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Tourer
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I wish you would have posted this in my obsolete SERT thread... I have had a vibration ever since I hit a rough crossing 4 months ago
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But you might still have other issues, maybe a motor mount or something.
All you can do is measure your runout to see if that is your problem.