<div class="FTQUOTE"><begin quote>Originally posted by: BigMc

well, The crank will cost me 75.00 to rebuild. The rod kit cost 50.00. Thats less than half what a new one would cost. Keeping the 230 alive is not as costly as one might think.

I was thinking about creating a photo log of this build. If there is a intrest, I can forward the file to anyone that wants them.





keep-em-alive</end quote></div>

I am interested! I love a good picture book!

 

keep a lookout on ebay for a hotrods crank kit i got mine from wiesco on ebay for 40.00 shipped

 

Alright kids, I NEED YOUR HELP! FINALLY kicked the big bore to life tonight, I haven't felt vibration like this since my Dad's 1960 something Pan Head Harley!!!!!!!!!!!!!!!!!!!!!!!
What did I do wrong?? 273 big bore kit, hot rods kit to match, stage 2 cam, valve springs to match, 32mm carb, and more, any of you that have been reading know what I have been doing. Is it the crank? OH CRAP!!!!!!!!!!!!!!!!! I think I put the "stock" crank in the the big bore motor!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Would the non modified crank cause this much vibration???

Any knowledge/info, as always is much appreciated. I have a call into my engine guru, but I love ya alls opinion. Gotta start labeling my parts better.............. SH@T!!! Fu%K!!!!DA*MN!!!! I think I screwed up again!

 

Did you have a 250 rod installed on 230 crank counters?

 

Correct, but I put the wrong one in! Machinist did something to the other one to make it work with 250 crank.

I just love making more work for myself.

 

aint 230 and 250 cranks the same?????????this is what i havee heard....if not same what is difference???

 

Same but different, is the way it was explained to me. Do be honest my machinist was using big words I didn't quite comprehend, but in a strange way, I git "same but different"!

I am going to read WAY back in this thread cause I think this was discussed b4.

Once again any help or info is ALWAYS appreciated.

 

Well, The 230 and 250s share alot of parts. The crank is not one of them. The counter weights and crank pin both carry a diffrent part number and the rod itself is not compatible between the 230 and 250. The 230 piston does not work with a 250 rod. The 230 piston has a 16mm pin bore. The 250's is 17mm.

The small end of the connecting rod is 17mm on the 250. The 230 is 16mm.
I can see only one reason the 250 crank counter shafts can carry a diffrent part number, the counter weights (on the 250) are slightly diffrent due to the extra weight of the rod small end.

This being said, there is no reason a machine shop cant adapt a 250 rod kit to 230 counter weights. If the big end is the same on both ,the 230 and 250, then it should work. After all, there is only one piston to move up and down in the bore. If the counter weights and connecting rod/piston combination are balanced, it will work.

I hope I havent confused the issue.


BigMc






<div class="FTQUOTE"><begin quote>Originally posted by: 270quadsportguy

aint 230 and 250 cranks the same?????????this is what i havee heard....if not same what is difference???</end quote></div>

 

<div class="FTQUOTE"><begin quote>Originally posted by: BigMc

Well, The 230 and 250s share alot of parts. The crank is not one of them. The counter weights and crank pin both carry a diffrent part number and the rod itself is not compatible between the 230 and 250. The 230 piston does not work with a 250 rod. The 230 piston has a 16mm pin bore. The 250's is 17mm.



The small end of the connecting rod is 17mm on the 250. The 230 is 16mm.

I can see only one reason the 250 crank counter shafts can carry a diffrent part number, the counter weights (on the 250) are slightly diffrent due to the extra weight of the rod small end.



This being said, there is no reason a machine shop cant adapt a 250 rod kit to 230 counter weights. If the big end is the same on both ,the 230 and 250, then it should work. After all, there is only one piston to move up and down in the bore. If the counter weights and connecting rod/piston combination are balanced, it will work.



I hope I havent confused the issue.





BigMc


Yeah, yeah, balancing, counter balancing, lightening, those were all the big words.............and more... I think the stroke was also changed with this kit??? Not just the bore?????? Once again, I am without a clue.










<div class="FTQUOTE"><begin quote>Originally posted by: 270quadsportguy



aint 230 and 250 cranks the same?????????this is what i havee heard....if not same what is difference???</end quote></div></end quote></div>

 

Ok, ive done a little more reserch on the crankshaft question. The crank/rod pin bearing (big end) is 2mm larger on the 250 than the 230. But the crankshaft to engine case bearings are exactly the same on both machines. For this to work, either the 230 counter weights must be machined to accept the 250 pin. Or you need to start with a 250 crank and use it in the 230 bottom end. Or, I guess you could take 1mm of meat out of the 230's piston pin end (small end) and hope for the best. I dont think that is a safe thing to do.
Size does matter after all............................................... ..DAMN.

Latter.

BigMc