Welded Crank question.

I am wondering how many people that have had their cranks welded had to have the crank trued up after the welding? I am putting a 1075 wiseco kit put in my 78 kz1000 and contemplating whether or not to have the crank welded.

First off crank should be completely disassembled inspected trued then welded.

You can't true an already welded crank without grinding out the weld and starting again.
Any reputable crank shop will disassemble the crank and after ensuring all the components are serviceable will weld up the pins during the re-assembly after making sure each web is in the correct position.
Final checks are done with an indexing rod and by mounting the crank on either V blocks or between centres to check for run out with dial gauges.
Some shops just stick an indexing rod through the little ends of a complete crank and weld the pins.
AVOID these shops as that method can cause the crank to warp with weld quality and penetration usually not sufficient to be of any use when you need it..

Does anyone really need a welded crank with a 1075cc kitted 78' engine on the street?
Seems a bit like over kill to me.

I had it done to the last one just so I wouldn't have to go in there again. After what I just went through I wish I could have had it done to the new one.
Steve

Yes remember these cranks are now getting to be 40 years old.

...1075 wiseco kit put in my 78 kz1000 and contemplating whether or not to have the crank welded.

Maybe a bit overkill on a that unless you are tuning it a lot.

Different cranks I know but I was advised the for a GPz 1100, going 1170 is fine but 1260 really needs a welded crank.

If it's not a 900 and you know the history of the bike with certainty and if it's been taken care of and if you are not going to be abusing the hell out of it and if you thoroughly inspect the crank tolerances and they are found to be good, then IMO might be ok with an non welded crank in a mild 1075 street motor. It really depends on the history of the bike and that's not something you often have a clear picture of unless you owned the bike yourself or some such situation.

I would never build a motor without new cam chain going in. I don't like master link chains so the crank always comes out. In the past 8 years I've only done two engines that did not get welded cranks. Both of them were stock rebuilds. All the rest, and there have been many, got at least welded cranks. The bad ones were sent out.

I have a .500 lift intake cam that's in 4 pieces that came out of a 1428 hill climb bike with an old but welded 900 crank that snapped in the middle. Yes it lived a hard life. The old small pin cranks are risky business in any large cc, ultra high performance application.

I don't generally find the pre MKII cranks to be twisted but most of the MKII cranks that I've seen are out of index and need to be fixed. When they are straight, in tolerance and just need welding we handle that locally. If they are out of index they get sent to Gardner Racing Concepts where they get a thorough going through. It's not cheap but they are ready for anything when Stan gets done with them.

I agree with DFIGPZ....they are getting old and as such need attention paid to them when inspecting them. We're all getting old..and need attention though:)

Larry, Have you ever had a GPz crank that is badly out, but was running just nice before the rebuild? Anyone?

Are the later GPz B cranks stronger?

Larry,

I think my bike fits your first description. I have owned it since it had 3600 miles, before that it was a friend of my dad's. The only reason it's apart now is to have the cam chain replaced. I found the cam chain tensioner was cracked last year and stopped riding it. It's always had regular maintenance. The motor only has 21,000 on it now. I really have no reason to suspect anything at all is wrong with the crank. The only reason I was considering having it welded it because it's out of the motor and I have the opportunity. I am starting to think it's overkill. I'm not planning on racing the bike. No other power adders on this bike either, very much stock.

Swest,
What's your story, Why do you wish now you had welded your crank.

Lastly, what does it typically cost, ballpark figure, to have a crank taken apart, trued and welded?

Cut and paste from the resident race bike guru (Rapidray) on The GS Resources...

There are only THREE places I will send a roller bearing GS crank for work, Pearson Racing in Ohio, Gardner Racing Crankshafts in Maine, & Accurate Crankshafts in Florida. I wouldn't send my lawnmower crank to Falicon!!!! The 3 above are the only ones I use & they know what they are doing, are honest & do good work.

Thanks for the suggestion. I think I am going to give Pearson a call and see how much it would cost to have them do a basic welded crank.