Why does this break then

[markfoggy]

Second one to let go this year and we're not the only team to have suffered with it.

Seems to start at the oil bearing, dowel hole or possibly the Stud bottom.

Propagates around the side and into the timing chamber. Oil loss is spectacular, certainly not safe for the rider if he doesn't bring it back to us quickly.

So, after the first one let go, we essentially just re-cased the engine. Now the crank has very little run out. It's EFE so welded by Suzki. Stuck on V blocks on outer bearings and a surface plate, we're only seeing a couple of thou across the other journals. Have we got a rougue crank here and a vibration issue.

First time it was assembled with APE studs. Second time, a standard stud was used in this position to ensure that it bottomed correctly, so you'd think that it can't be pressure at the bottom of the stud landing or distortion across the thread.

What the actual fuck is going on.

Thoughts?

 

[vizman]

fatigue in old cast caused by power from the motor/frame stress, mixed up with the cases eventually passing their yield.

[Swiss Toni]

Aye, all these old cases have been around for quite a while! MIght be a good idea, before the next  build, to have the cases Magnafluxed?

[vizman]

mix in prolonged high temp or rapid cooling with old cast and something's gunna' pop.

[KATANAMANGLER]

Does seem suspicious that they both went in the same place. As you say it could be the crank as it's the common denominator .  What sort of power is the engine putting out?

[markfoggy]

So is this a known design flawed area where they pop on a regular basis, or is it something that we're contributing to?

Magna-fluxing only works on ferous metals doesn't it? Don't think that we're seeing previous damage contributing.

We're pretty sure that we can't detect any real stress raiser in this area and alloy tends to normalise over extended periods, we could probably get it to re normalise over a period of time just by getting it hot, cooling slowly and leaving it alone for a month or 2. If it was a cast iron block I'd be thinking ship it off to Siberia for a few years and let it weather.

[markfoggy]

Does seem suspicious that they both went in the same place. As you say it could be the crank.  What sort of power is the engine putting out?

About 140 something, we're not chasing horses and being really conservative with rev limits. Mertens given a bollocking this weekend for going to 8500.

Lap-times are generated by Torque in our experience.

It's 1230 btw, not stoopid Shirely?

[KATANAMANGLER]

I've had quite a few of these engines normally running at around 125 BHP and I have never seen one go there. It's the drag boys that test the cases to destruction and I'm sure they would be a better source of data on the standard cases' weakest points but then they are running 200+ BHP.

[KATANAMANGLER]

I run 1230 on my EFE engine in my Kat. It gets caned mercilessly and I've never seen any signs of a problem in that area. I have had another 1230 before that as well as a couple of standard motors and I've never seen that..  What torque settings are you using on the head?

[vizman]

and I would've thought torque is the thing that could do this?

[vizman]

stress and old age, fooks with everything

[vizman]

I would say prolonged stress as the drag boys n' girls are doing short periods of stress....

...and since the classic boys n' girls are the only people subjecting old cases to endurance racing they are the only ones who are gunna' find this problem....

...most racers race new stuff and move onto newer stuff long before their stuff becomes old stuff.....

.....no doubt in a few years time the air cooled boy's n' girls on this site will start discovering the same issues, and few more years after that the oilboiler owners.....

or, you've just been unlucky and got some duff cast cases

or, a mix of fatigue/incorrect settings/stress/heat/blah blah blah

 

[markfoggy]

stress and old age, fooks with everything

Yeah I know, tosser.

I've been smokin for 40 yrs and there's nothing wrong with my lung.

Can we stop stating the obvious now, please,  I want solutions, goddamit.

 

[vizman]

have you tried switching it off and then back on again?

[markfoggy]

I run 1230 on my EFE engine in my Kat. It gets caned mercilessly and I've never seen any signs of a problem in that area. I have had another 1230 before that as well as a couple of standard motors and I've never seen that..  What torque settings are you using on the head?

Torque is not tractor tight, by this I mean do it up until it snaps and then back it off a 1/4 turn.

I've not asked Russell specifically, but I'm guessing 25Nm. The guy's been building World Endurance engines for 30 years and been quite successful at it. Doubt that he'll have lost his touch even if he's going by feel. Having said that his 3/8 Snap on torque wrench hasn't been calibrated for a good few years. I found that a fresh Norbar with calibration certificate (according to Russell he's never heard of them and anything that you buy of the internet is just chinese crap) is about 1/2 N stiffer so he'll be under as opposed to being over.

[markfoggy]

have you tried switching it off and then back on again?

Yup, tried that, oil still comes out.

 

 

[vizman]

 

Can we stop stating the obvious now, please,  I want solutions, goddamit.

 

climb down off your high blackn'decker work bench, we're hardly going to solve this with string theory...

  

[markfoggy]

Lidl's copy B&D workbench pls.

So are we all doomed. 

I was kinda hoping that we'd fucked up somewhere.

[vizman]

Lidl's copy B&D workbench pls.

So are we all doomed. 

I was kinda hoping that we'd fucked up somewhere.

sorry

not necessarily

you might have

[vizman]

on the plus side your team may have discovered the limits of 4 decade old Suzuki aircooled motors.....not much consolation, and I hope it's not the case [no pun intended] because I'd like nothing more than seeing a Suzuki based bike go on representing, and your team finding either the cause or even better a solution....one that you'd be willing to share.

keep on pushing that 2nd class envelope

[KATANAMANGLER]

Torque is not tractor tight, by this I mean do it up until it snaps and then back it off a 1/4 turn.

I've not asked Russell specifically, but I'm guessing 25Nm. The guy's been building World Endurance engines for 30 years and been quite successful at it. Doubt that he'll have lost his touch even if he's going by feel. Having said that his 3/8 Snap on torque wrench hasn't been calibrated for a good few years. I found that a fresh Norbar with calibration certificate (according to Russell he's never heard of them and anything that you buy of the internet is just chinese crap) is about 1/2 N stiffer so he'll be under as opposed to being over.

Generally speaking those head studs just stretch anyway but it sounds like your under at that rather than over. BTW didn't mean to imply your man was without mechanical finesse. I'm sure he has forgotten more than a civilan like me will ever know. It was just a question in the interests of establishing why the stud housing is cracking. I once set a torque wrench to Lbs ft while reading a Nm table lets just say I never had a leak on that head 

[markfoggy]

Sharing is a given.

Big up the old lump. 2nd yr of FIM Classic Endurance Championship domination. K's have had their day, and some. 16v's rock.

Back on subject though, that lump had only about 2 hours max running on it, lots of that was only running in (not entirely sure that thorough bread race jockeys actually listen to anything, more selective hearing that wimmin in my experience!) . It's not like we'd grenaded it after a whole season. 

[markfoggy]

Generally speaking those head studs just stretch anyway but it sounds like your under at that rather than over. BTW didn't mean to imply your man was without mechanical finesse. I'm sure he has forgotten more than a civilan like me will ever know. It was just a question in the interests of establishing why the stud housing is cracking. I once set a torque wrench to Lbs ft while reading a Nm table lets just say I never had a leak on that head 

As it goes though, we think that it's not starting at the thread base of a cylinder stud. seems more likely to be coming from where  the  dowel locates the cylinder. New dowels as well, rarely use second hand ones. I've just got back from the race meeting and don't have one to hand, but this looks to be a low pressure oil route  as well.

There's definitely something going on here. Hence taking it to the font of wisdom.

[vizman]

and at the risk of stating the obvious again questioning why a 40 year old second hand lump of mass produced cast pig alloy [forgive me o' lord of Hamamatsu] isn't up to the abuse of being taken past it's initial design seams to be answering your own question...along with possible incorrect torque settings......or miss-matched internals.....or damaged/out of spec internals.

unless you know the full history of where all your second hand parts have been and what they've been up to, i'll keep stating the obvious, and in no way trying to be a smart arse. [although it may be read as such]

 

 

 

[markfoggy]

Just 'cause you own a real WorkMate eh!