How's this for a nights work?

[ewok]

I'm putting another post up! After reveiwing this whole thread i have a few important points to make. (1)this crank was fitted into three sets of cases,it didn't fit right in one of them!(2)this set of cases is rough, but the stock yamaha crank fit perfectly,so it did in all the other ones too!(3)I shouldn't have to justify myself but i will because i have always been held to a higher standard.My father is a highly renowned swiss engineer who specilizes in fracture mechanics testing.He does mostly goverment contracting in the areospace-aircraft field.His customers include northrup grumman,boeing,cesna,pratt-whittney,mcdonald-douglas ect.When they are having a problem with a b-2 stealth bomber, they call my father for help.I have done measurment and fatige crack growth measurment for my fathers engineering firm, for companys like boeing for example.I have helped figure out design flaws in our nations top weapons.Feed back from a guy like me is INVALUABLE!!!!!!To be second guessed in this whole matter has been very insulting to me!!! I will definetly be a little more selective in who and how i do bussiness with.I think for now this is enough said.!!!!!_________________E..:frown:

 

[sflsurfrider]

I have done measurment and fatige crack growth measurment for my fathers engineering firm, for companys like boeing for example.I have helped figure out design flaws in our nations top weapons.

but you couldnt figure out how to put a crank in a set of cases? :haha:

j/k

that was wrong of me.:smashfreakB:

 

[john zigler]

thank you gregg for all of your replies.

i will say, this thread makes me go hmmmmmmm...........

scott, any news on the new crank yet? does it fit?

zig

 

[Mouthfulloflake]

Ewok,

your post confuses me a bit.

IM not picking sides, or stirring anything, but are you talking about runout or TIR?

when you say 0.0015 at its smallest point, and 0.0035 at its largest point?

 

[Greg Pickren]

ewok,

I personally looked at the crank laby again this morning and I can't find the run out that you are talking about. Keep in mind that the ID clearance between the crank pin and the laby is 0.002" to 0.003". It is not a slip fit, it is a loose fit. The crank pin turns such that it "floats" in space through the laby. You can actually move or rock the laby a couple of thousands each way as it is not tight on the pin and this is normal. The critical dimensions are the trueness of the crank, the OD of the bearings, the ID of the case bearing surfaces, and the alignment of the bore within the case. The purpose of the laby is to limit the flow of mass (gasses) between the cylinders through the crankshaft bearings. It is not a "riding" surface. So even if there was a little run out (which we can't find on this OE laby), it would not matter if it did not make contact when the crank was spinning.

I am sorry that you and Scott are not happy with SBT. We try our hardest to make a good product and stand behind it with the best warranty and the best customer support. Unfortunately, sometimes it's not enough. I hope you guys have better luck with the new crankshaft and refurbished cases.

Greg Pickren
SBT

 

[sflsurfrider]

what a guy

 

[Idok]

:noevil:




the buildup of yamabond is there from the last time we assembled the motor.......Butti, E and motosurfer are anal about surfaces and have engrained proper re-surfacing on every assembly into my skull...



Everyone on location saw E take those measurements repeatedly....he worked around the axis from at least a dozen points and repeatedly came up with the same #'s....different instruments and observers will many times come up with different data.......



E's machinework speaks for itself.....All of us are running his motors with outstanding longevity....









Ill put this motor into service ASAP and we'll see how she goes.....

 

[Greg Pickren]

Scott,

I hope the next build works for you. The odd thing about the case sealer buildup is that it was only on the bottom half of the case, not the top. It struck us as odd that one half would have been clean and not the other. The top half looked like hell, but there was no case sealant on it. This won't be a problem for the next build because we were able to clean the hardened case sealer (looked like Yamabond) off the surface.

As for anyone being anal about case surfaces, if they truly were, this case would be thrown away.

Greg Pickren
SBT

 

[Mouthfulloflake]

Greg,

thanks for your input on this thread.

and, Ill take all those cases you guys throw away, just box them up and let me know how much to ship.

 

[tom21]

ditto lake.

 

[douglee25]

E,

I don't think anyone is doubting your expertise. You brought up a case where a crank was bad. Like Greg did, I too would measure the crank, cases, etc to double check where the issue lies. Just because you have a diverse background doesn't mean that you or someone else you work with could have missed something. Don't take offense to it. Everyone was just trying to help to get to the root cause.

Doug

 

[ewok]

crank issues

Im putting this whole matter behind me to begin with! Greg, thank you for replying in a professional manner and we all appreciate you sending us a new crank and cleaning up the cases.I have been doing bussiness with sbt for a long time and always have been very happy with your products and excellent service.It's nice to know that the top-dog will become involved in customer relations if needed because most companies wouldn't do the same.Mouthfulloflake--to answer your reply, we measured the o.d of the labby not the runout. When we were having interference issues it took awhile to figure where it was coming from.The labby is the only part that was not the same readings as the stock yamaha crank, this is why i took about 10 readings of the o.d. of the labby and saw that was not round.The cases are quite bad and there is definetly damage from a motor failure which happened before idok owned the motor.looking forward to seeing the new crank and building a new motor for scott (so we can go destroy it again in the surf!!!!)
Untill next time< let's all go riding and have a great time, isn't this why we all ride anyway????eveyone take care!!!_________i'm out_____EWOK>>>>:sneaky:

 

[tom21]

so will you guys let us know what looks to be done to the crank and cases and let us know if it fits and what exactly the problem was?

Unless I am confused, crank did not fit the case because the laby was out of round? and rocked ( because of the laby in the middle-which is located by the pin) SBT found nothing wrong with the crank but finds the case has yamabond build up in the front and rear. Did I miss something here? Not pointing fingers just trying to understand what is being discussed. Is the crank not installed right or is the rocking not being seen by both parties. it fits or it doesn't? I'm lost.

 

[Idok]

so will you guys let us know what looks to be done to the crank and cases and let us know if it fits and what exactly the problem was?

Unless I am confused, crank did not fit the case because the laby was out of round? and rocked ( because of the laby in the middle-which is located by the pin) SBT found nothing wrong with the crank but finds the case has yamabond build up in the front and rear. Did I miss something here? Not pointing fingers just trying to understand what is being discussed. Is the crank not installed right or is the rocking not being seen by both parties. it fits or it doesn't? I'm lost.

that crank ABSOLUTLY rocked in the cases.....when E DELIVERED it to SBT the first time he showed them and EVERYONE saw it rock (greg wasnt there at that time...)




the buildup of yamabond...was there from assembly #3 of the motor..


I still question the measurements......E's instrumentation (vernier micrometry) is THE most accurate way to measure....


ALL of our OE cranks dropped into these cases (as well as 2 other sets) like butta!!!!! however, the sbt crank would not fit into ANY of the cases without rocking....




i got a different crank last night from them, as well as my cases back.......going to try and get this motor built and dropped into a ski asap.....we'll see how THIS crank fits and will definatly get back with everyone.....


i still however did not receive any of the seals or gaskets mentioned above.......

 

[tom21]

so SBT never found anything wrong with the "rocker" crank? They sidestepped the prob and gave you a new crank? how do we know if its the crank or the case? Yeah its great they stand behind their products but I am all geeked out by the engine building and want to get to the cause not the solution.

thanks for bearing with me

 

[Idok]

so SBT never found anything wrong with the "rocker" crank? They sidestepped the prob and gave you a new crank? how do we know if its the crank or the case? Yeah its great they stand behind their products but I am all geeked out by the engine building and want to get to the cause not the solution.

thanks for bearing with me

well, they measured it with a digital caliper..........



like I said...EVERY OEM yami crank we had (I personally have 3) fit into the cases PERFECTLY....let me say that again...PERFECTLY..with no problems, no rocking, perfect sealing...even dirty ones that havent been cleaned since disassembly


its not the cases

 

[tom21]

I completely hear what you are saying, What did SBT tell you was wrong? No expanation just sent another crank with a sorry and no gaskets?

 

[butti]

I completely hear what you are saying, What did SBT tell you was wrong? No expanation just sent another crank with a sorry and no gaskets?

ummm........did you read this thread?

 

[tom21]

Yes, yes sir I did. And I am not trying to start anything, I don't know the people involved personnally, have done business with SBT with no issues, and am in every way possible that I can think of not biased. I just want to understand how someone with obviously way more technical skill than is necessary can find that they cannot fit the crank properly and then SBT cannot find the SAME thing. If the crank fit with no issues why did they not just drop it in and ship it back with a note saying,"here it works"? If it was bad, why not tell us what the problem was?

Sorry to keep dragging this on and I apologize if I missed, forgot, misread, or plain just don't see that it was spelled out already. I am just trying to understand what the PROBLEM was. There must have been one if they sent a totally different crank. right?

 

[tom21]

well GP did say they sent another one out but my question is he could find no problem and they could fit it why not ship it back? here fixed it? or just say it looks like xxxx happened, here is your reason. Now it looks like they are hiding something instead of just coming clean.