Stroker bearing failure

[entropy]

apart from all that i would carefully check the oil pump...slightly faulty ones can cause instant pressure falls which in a time manner can ruin a perfect crank...have seen that happen many times...

 hmmmm...
i log oil pressure bc i'm concerned about it, but don't see any pressure drops...

[entropy]

From what it looks like to me is that your having a problem with the rod rocking too much....its hard to tell from the pick coloring...
The outside of  the bearing surfaces look to be more worn than the inside...Usually caused by  detonating, piston hitting the head, too much side/side clearance on the big end of the rod...
just me 2 cents from what the pics look like

i have no doubt that some sort of rod shenanigans are going on, but apart from that aspect, its those mottled/crazed patches i'm looking at.

[whtrthanu]

the patches are from suzukis shitty soft bearings...it happens from the fuels also....oxy fuels contaminate the oil making the bearings flake.........it sucks, been there.........send the bearings to calico coatings it helps alot.....
On the good side they are almost done with a heat treated bearing for the zuks..........better late than never........
it will be like the cryoed clevite  ugly as hell but they work

[TRNorBRN6001]

Kawi bearings          

I your opinion, how do the coated bearings look after abuse?

[whtrthanu]

alot better......

[entropy]

the patches are from suzukis shitty soft bearings...it happens from the fuels also....oxy fuels contaminate the oil making the bearings flake.........it sucks, been there.........send the bearings to calico coatings it helps alot.....
On the good side they are almost done with a heat treated bearing for the zuks..........better late than never........
it will be like the cryoed clevite  ugly as hell but they work

I don't know about Calico, but 've got a smokin' deal with WPC, and Izumi is surface treating+ coating set of bearings next week for free!  Woo-hoo!

If WPC doesn't work out, i'll try calico as you and TRNorBRN suggest. Thanks for the tip.

This 1427 Kwak motor is my Senior Science Fair Project; I try stuff, brutalize it on a FactPro dyno, then tear it down every 2-3 weeks.

DarkFalcon's tips on head work recently got me hp that I NEVER thought I would see, but longevity of parts is a work in progress

[strokedgsxr]

Falicon journals are to soft. Always have the crank nitided. I believe all APE cranks are done. Falicon should catch on before they loose any more business. Call it how ever you want but the proof is in the puding so they say. I will never run another Fcon crank weldup or repair unless it has been nitiried. Sure sucks to do a crank repair and have it come right back apart on the same journal.

[Jay]

If you have a crank done by someone else besides us, we can nitride it.

Jay

[crazybill]

I built a zx14 motor this weekend and used calico coated bearings in it . the coating is so slick when i plastigauged everything the plastigauge didnt stick to the bearings AT ALL ! not even a film to wipe off the bearing . I found that pretty interesting...

[entropy]

I built a zx14 motor this weekend and used calico coated bearings in it . the coating is so slick when i plastigauged everything the plastigauge didnt stick to the bearings AT ALL ! not even a film to wipe off the bearing . I found that pretty interesting...

cool!!!

please give an update when you pull the motor down, and i will do likewide with the WPC treatment/coating.
compare & contrast!

[crazybill]

this guys hoping it wont have to come back apart anytime soon ... its squeezed real tight and he is throwing a 100 shot wet at it so we'll see . Dont forget where Im at too... this bike wont see a dragstrip for 2-3 months .

[entropy]

this guys hoping it wont have to come back apart anytime soon ... its squeezed real tight and he is throwing a 100 shot wet at it so we'll see . Dont forget where Im at too... this bike wont see a dragstrip for 2-3 months .

i hear ya on not being able to get to the track.

Here in Houston, temps plunged into the lo 60's on Sun; no way i could brave those temps!

[crazybill]

 

[show2ime2000]

I built a zx14 motor this weekend and used calico coated bearings in it . the coating is so slick when i plastigauged everything the plastigauge didnt stick to the bearings AT ALL ! not even a film to wipe off the bearing . I found that pretty interesting...

You don't use a dial bore guage??

[entropy]

i don't know about crazybill, but i stopped using plastigauge 2 years ago and starting using a boregauge on the mounted bearings.

I was REAL happy with the repeatability of the measurements until this weekend.

I did some tests (thanks to TChin) which showed that those lil scratches the boregauge makes in the bearing surface are about 1.5-2.0+/- tenths deep, and that the boregauge direct measurement of the mounted bearing is about 4 tenths bigger that the actual ID.

This means ALL my carefully obtained rod & main clearance data from the last 2 years is about 4 tenths larger that I thought it was.

I always thought it was odd that even with the tightest shells i couldn't get main clearances under about .002"

so..........
when i thought i was running 20-22's on mains and 25-27's on rods, i was prob running 16-18's on mains and 21-23's on rods.

Performance-wise, I really don't think it means shit to a titmouse, but it was an eyeopener to me.

[crazybill]

guy showed up with plastigauge and insisted I use it... what was I going to tell him... no ?

Ive been a machinist for almost twenty years... I have enough precision measuring equipment to render plastigauge dinosaur shit , but if it makes my customer happy to see me use it... im all about making people happy 

did you have set-rings made up for your target diameter for your bore gauge ? remember , your measurment is only as good as your referance dia.
I'd love to get an air-gauge and set-ring set-up made up . that would be the most precise way to go . I used to make oil pumps for caterpillar and with air could measure to w/in .000025" (25 millionths) without actually touching the bearing .

[entropy]

crazy bill,
man o man, you have great experience!

I don't have set rings, but i do have a digital Mitutoyo mic which reads to 1/2 a tenth.  I set and lock the Mit-mic on the target then calibrate my Mitutoyo bore gauge to 0 at that target.  The Mit-bore gauge has  relatively wide .0001" graduations and i can pretty easily reproduce within .0001".

It's the depth of penetration of the boregauge into the bearing surface which surprised the hell outa me!

[TrickTom1]

 

[mike46]

crazy bill,
man o man, you have great experience!

I don't have set rings, but i do have a digital Mitutoyo mic which reads to 1/2 a tenth.  I set and lock the Mit-mic on the target then calibrate my Mitutoyo bore gauge to 0 at that target.  The Mit-bore gauge has  relatively wide .0001" graduations and i can pretty easily reproduce within .0001".

It's the depth of penetration of the boregauge into the bearing surface which surprised the hell outa me!

You have to go very easy on the spring preload or you will gouge the crap out of the bearing

[mike46]

guy showed up with plastigauge and insisted I use it... what was I going to tell him... no ?

Ive been a machinist for almost twenty years... I have enough precision measuring equipment to render plastigauge dinosaur shit , but if it makes my customer happy to see me use it... im all about making people happy 

did you have set-rings made up for your target diameter for your bore gauge ? remember , your measurment is only as good as your referance dia.
I'd love to get an air-gauge and set-ring set-up made up . that would be the most precise way to go . I used to make oil pumps for caterpillar and with air could measure to w/in .000025" (25 millionths) without actually touching the bearing .

I heard Honda used the air guage method for their race bikes back in the 60's.

[TRNorBRN6001]

Karl, it looks like you'll be getting a new toy (air gauge). Maybe they can
cut you a deal on the one from the 1960's, cause it sure don't sound cheap!

[whtrthanu]

I had a customer recently say that plasti gauge was more accurate than a mic....
He had a bearing failure and I was redoing the motor, He said the shop he was using for years usung nothing but plasti gauge and they build the fastest stuff around period.....

Now Im not going to say the reason that he had a bearing failure was from the plasti gauge,or that the 12k miles on the stock rods had something to do with it either.....

I find it funny as hell that at least half the shops out there cant even read a mic..
If you were putting a car motor together you could get away with using guesta gauge, because the clearances are much larger than the motorcycles.....How the hell do you measure .0001-.0002 with a piece of plastic...
I also just recently bought a big block from a well know builder that designed and ran off a few sets, I cant tell you how many people swore by his work being state of the art precision......
Well needless to say I am very unhappy with the block, and his work.....The bore centers arent even right, and im not talkin about 2 or 3 thou, im talkin like .015...And than when i spoke to him about it, his excuse was that it for unshrouding valves, ya, ok so why the hell are they all different.............thats when I heard the crickets.........
Very few people can do machine work correctly, if there doing it cheap, its for a reason..............

[THE ICE MAN]

crazy bill,
man o man, you have great experience!

I don't have set rings, but i do have a digital Mitutoyo mic which reads to 1/2 a tenth.  I set and lock the Mit-mic on the target then calibrate my Mitutoyo bore gauge to 0 at that target.  The Mit-bore gauge has  relatively wide .0001" graduations and i can pretty easily reproduce within .0001".

It's the depth of penetration of the boregauge into the bearing surface which surprised the hell outa me!

Karl get yourself a boregauge with different anvils so they will not dig in the bearings.
Sal.

[entropy]

crazy bill,
man o man, you have great experience!

I don't have set rings, but i do have a digital Mitutoyo mic which reads to 1/2 a tenth.  I set and lock the Mit-mic on the target then calibrate my Mitutoyo bore gauge to 0 at that target.  The Mit-bore gauge has  relatively wide .0001" graduations and i can pretty easily reproduce within .0001".

It's the depth of penetration of the boregauge into the bearing surface which surprised the hell outa me!

Karl get yourself a boregauge with different anvils so they will not dig in the bearings.
Sal.

hey Sal,
i will sure get some anvils with bigger diameter ball bearings in 'em, but i don't measure the installed bearing anymore. 

I have converted to measuring the rod or case bearing mount (without bearings installed) after tqing it, then measuring the thickness of ea shell and coming up with a calculated ID.  This seems to work fine.

[whtrthanu]

thats the way I do it also works fine, no damage to the bearing.....