My bike at present, FAILURE

V

Vegard

Joined Oct 2003

252 Posts | 1+

Norway

Discussion Starter
• Aug 11, 2005

• #1

So, here's what's left of it....

On Yesterday's supermoto practice, the engine stopped with a loud bang. The thing is that the crank may be moved on one side only. Sounds expensive to be honest....

We'll open the engine on monday, and see... I'll let you know.

On a second note, is there a supermoto performance upgrade camshaft?? Will a different cam ( Maybe one of LINEAWEAVER'S?) give me more power without decreasing reliability? I'm thinking of having the head ported as well.
What about valves? Is there anything to gain there?

 

madero

Joined Sep 2004

186 Posts | 0+

• Aug 11, 2005

• #2

valves

read my former post about bigger valves,power will be gained.

 

S

sandskipper

Joined Aug 2003

517 Posts | 0+

Chandler, AZ, USA

• Aug 11, 2005

• #3

Vegard,

A Lineweaver cam will benefit you in both power and reliability. Dale's cam has proven to draw the power linear over the entire RPM range as well as give a few more ponies. Also the lobe profile on the cam is smoother to reduce harshness on those valves for better wear on all those moving bits and pieces. I'm sure Dale could give you all the numbers and such but this is lamens terms.... hope this helps. Dale has been doing some development on some Ti valves and such also, you should give him a call for all the info.

Regards,

 

V

Vegard

Joined Oct 2003

252 Posts | 1+

Norway

Discussion Starter
• Aug 18, 2005

• #4

So...
Both main bearings let go, and the crank snapped. That's cutting a long story short....

The warranty covers everything, so I'm a happy chap.

 

Taffy

Joined Nov 2001

17K Posts | 774+

Ely, England

• Aug 18, 2005

• #5

is that an early mini in the garage?

regards

Taffy

 

V

Vegard

Joined Oct 2003

252 Posts | 1+

Norway

Discussion Starter
• Aug 18, 2005

• #6

It's a 69, but I've got four

 

Taffy

Joined Nov 2001

17K Posts | 774+

Ely, England

• Aug 23, 2005

• #7

i fell out with the old man as a young lad and even though i still lived with the family i did up minis in the back yard. a very strange situation!

i bought and sold 12 in a year. browns, whites, mustards and even a black one. it wasn't the profit; chripes it wasn't that they didn't need any work!!! they needed tons! but you could always sell it the moment you had 'tarted it up'.

yep-i knew a bit about minis :wink:

regards

Taffy

 

V

Vegard

Joined Oct 2003

252 Posts | 1+

Norway

Discussion Starter
• Oct 26, 2005

• #8

And here two pictures of the damage:

No wonder it stopped...

The imorter/local dealer have been fantastic about it, just let me say that!!!

 

B

BD

Joined Sep 2002

212 Posts | 0+

Great Northwest

• Oct 26, 2005

• #9

Those are good pictures of a bad thing. I don't see a chamfered edge at the top end of the radially-drilled blind hole. It also appears to be a very brittle failure. Do you have a means of measuring hardness, just out of curiosity? I understand the bearing possibly went first, but I still like to see better machining detail than that. Nice to hear that the dealer is on your side. Regards, BD

 

LINEAWEAVER

Joined Jul 2001

3K Posts | 1+

El Sobrante, Ca. 94803

• Oct 26, 2005

• #10

BD said:

Those are good pictures of a bad thing. I don't see a chamfered edge at the top end of the radially-drilled blind hole. It also appears to be a very brittle failure. Do you have a means of measuring hardness, just out of curiosity? I understand the bearing possibly went first, but I still like to see better machining detail than that. Nice to hear that the dealer is on your side. Regards, BD

Click to expand...

Hi Brad,
Not the first Husaberg crank pin to crack through the oil hole. You are correct regarding the lack of corner dressing. High RPM and the axial balance weight also contribute.

Dale

 

V

Vegard

Joined Oct 2003

252 Posts | 1+

Norway

Discussion Starter
• Oct 27, 2005

• #11

As far as I know, this rarely happens on the short strokes. Its a 450. I must admit I only use it for supermoto, and I do rev it.

I don't have any means to do a hardness test, and it was said that the importer possibly wanted the crankshaft in return.

Both mains had gone, all happended within 100meters.

As I was driving back tio the pits, I heard a small knock before I shut the bike down, didn't think about it really. Then 20minutes later, I started it, NO sounds. Second bend in the supermoto track, I get what sounds like big end failure on a car (at 3/4 max revs) it suddenly goes BANG, and freezes completely.

I could not have shut it down before it went bang, that's how fast it happened.

 

B

BD

Joined Sep 2002

212 Posts | 0+

Great Northwest

• Oct 27, 2005

• #12

Crank failure. The bearings, (and probably lots of other things), were secondary damage. A carburized crank pin with a tough core and correct machining will greatly limit or eliminate that particular failure mode. BD

 

B

BundyBear

Joined Apr 2003

1K Posts | 3+

Newcastle, NSW, Australia

• Oct 27, 2005

• #13

Just curious, Dale mentions it is an oil hole. Isn't it blind? If it is blind, how does it do anything other than just cause a stress raiser? I see there is a centre mark on the end of the pin but no evidence of a cross drill into the blind hole?

I see what I assume is the oil exit hole about half way along the pin length at 90 degrees to the one that started the crack. How does the oil actually get through the pin?

 

V

Vegard

Joined Oct 2003

252 Posts | 1+

Norway

Discussion Starter
• Oct 28, 2005

• #14

If you look hard on the third picture you can see a VERY small hole on the iside of the crank journal. Where would the big end beating be fed if not here?

 

V

Vegard

Joined Oct 2003

252 Posts | 1+

Norway

Discussion Starter
• Jul 2, 2006

• #15

As a reference to this:
http://www.husaberg.org/modules.php?nam ... pic&t=4296

I just took the flywheel cover off, to find that the flywheel itself as disintegrated. This has made the entire assembly unbalanced and I guess the mains have died because of this. Is this plausible?

Maybe the flywheel died last time the crank snapped, and that this was not adressed at the last rebuild?

I'll get some pictures up shortly.

 

V

Vegard

Joined Oct 2003

252 Posts | 1+

Norway

Discussion Starter
• Jul 3, 2006

• #16

Just to add, this is 11 hours of riding after the previousl thorough rebuild.

So, what causes the flywheel to die like this?

 

Taffy

Joined Nov 2001

17K Posts | 774+

Ely, England

• Jul 3, 2006

• #17

your mains went first and that made the flywheel weights catch and smash up.

mains first, flywheel second.

regards

Taffy

 

V

Vegard

Joined Oct 2003

252 Posts | 1+

Norway

Discussion Starter
• Jul 4, 2006

• #18

Do you reckon? What would make the mains die after just 11hours (just checked) of running? This engine has also had the 05 treatment ie one roller and one ball main instead of the 04's two ball bearing mains. The engine has NOT been used differently than last time.

35 hours it lasted from new.. Now this again.. Gutted!

Now where did I put that Yamaha sales brochure...

 

Taffy

Joined Nov 2001

17K Posts | 774+

Ely, England

• Jul 4, 2006

• #19

well something was wrong before you started. you can tell things from all items such as blueing means heat and no oil.

you may have a change in colour of some items?

also one side went before the other - but which. the rollers won't put up with anything that isn't right.

i would check for axial looseness - that's from left to right across the crank. you'll need a good man to spot the problem but it is possible.

dale often used to ask for owners to 'post photos....

regards

Taffy

 

V

Vegard

Joined Oct 2003

252 Posts | 1+

Norway

Discussion Starter
• Jul 7, 2006

• #20

I just found this:

Not quite the way it should be.

Apart from this, it all looks OK. I haven't checked the ball bearing, but that will be changed as a matter of course.

Still don't know why though!