Cracked Case Last Night

[one2dmax]

Well, been doing some tuning on the bike to get it up to par before the big races in two weeks. We had taken it to the dyno day in Topeka and with v-boost closed off and 162.5 main jets (and our jet kit) I was way rich and pulled 116 hp 84 torque. We changed the jets to 155's and opened the v-boost up full time which brought the power up to 133rwhp but now I was way lean (way lean). So took it home and played with it there. Changed back to 160's which seemed to make the top end great but still lean on the clip setting. Swapped the stock needles which were already shimmed out for stage seven needles. This helped some but as I was taking it on the test ride I had a bit of trouble.

I had been running a Barnett clutch setup which was slipping at the track under hard acceleration and power shifts. I went back to the double d setup which grips considerably better.

On the second test pass (on my way to vote), I turned onto the main street and gapped it. When I hit second the shock load from power shifting caused a huge bang. It ended up the cases where the middle driven gear are cracked out ruining the cases. This is the second time I have seen it. The last time was on a 1500 engine making almost 170hp. I know I am no where near that but figured I was very close to 140 with the tuning.

So - I will be putting in a temporary engine in the two-face bike until I make it bigger better stronger!

Check out the crappy cell phone pic.

Sean Morley

 

[Dreamster66]

Thats a shame Sean

 

[shawn kloker]

Well, been doing some tuning on the bike to get it up to par before the big races in two weeks. We had taken it to the dyno day in Topeka and with v-boost closed off and 162.5 main jets (and our jet kit) I was way rich and pulled 116 hp 84 torque. We changed the jets to 155's and opened the v-boost up full time which brought the power up to 133rwhp but now I was way lean (way lean). So took it home and played with it there. Changed back to 160's which seemed to make the top end great but still lean on the clip setting. Swapped the stock needles which were already shimmed out for stage seven needles. This helped some but as I was taking it on the test ride I had a bit of trouble.

I had been running a Barnett clutch setup which was slipping at the track under hard acceleration and power shifts. I went back to the double d setup which grips considerably better.

On the second test pass (on my way to vote), I turned onto the main street and gapped it. When I hit second the shock load from power shifting caused a huge bang. It ended up the cases where the middle driven gear are cracked out ruining the cases. This is the second time I have seen it. The last time was on a 1500 engine making almost 170hp. I know I am no where near that but figured I was very close to 140 with the tuning.

So - I will be putting in a temporary engine in the two-face bike until I make it bigger better stronger!

Check out the crappy cell phone pic.

Sean Morley

Sean,Do you feel the venture cases were weaker than vmax?Or just too much torque?

 

[one2dmax]

Venture cases are fine, Problem was excellent traction, good power, 100% grip on the clutch, banging the gears, and generaly long term fatigue.

Sean

 

[mabchewy]

Sorry to hear about that Sean, I know how you feel.

 

[Rusty McNeil]

Jeez that sucks Sean, hate to hear it. at least it happened to someone with the resources to get it back together alot easier than most of us. Good luck with it......

Rusty

 

[shawn kloker]

Could probably be tigged back up.

 

[Bill Seward]

How about that JB weld stuff?













not really...

 

[Buster Hymen]

How about that JB weld stuff?



not really...

Well.. maybe.. isn't there a story on the package about someone repairing a diesel engine block? I don't think I'd trust it... but still...

 

[shawn kloker]

A good welder could tig that and it would be stronger than before.Of course it would have to be disasembled,baked and bolted tight then welded.

 

[Bill Seward]

Well... You're gonna have to disassemble it anyway, and I'd bet a case costs a lotta dough, If it was my bike, I'd find the best welder in town, and take a shot!

 

[one2dmax]

I have seen one that was welded up and it was holding but I have a few spare cases around so it's going to be simpler for me to just swap it all over. I hate to try that repair and have it go bang even harder.

I will probably just move everything over to a 1300 block this time and see what we get out of that combo.

Sean

 

[Bill Seward]

This may sound dumb, but what do you mean by a 1300 block?
Venture?? I figure the Max and Venture cases are almost identical excepting the bore size, right?

 

[one2dmax]

There were 1200 Venture blocks from 83-85 (I used an 83 case set) and 1300 motors from 86 on up (93 i think). There are some differences between the early cases (mostly simple stuff like a cooling line to the stator in the later models) and transmission stuff (which was upgraded in the max and it in 86).

Sean

 

[shawn kloker]

Sean,How are you determining what crank,rod,and counterbalance shaft bearings to use with all the swapping?

 

[one2dmax]

crank, rods, counterbalancer (not 100% needed) are in fact the same with few changes. I don't even have a counter balancer in this engine. I probably won't ever do that again but it did work fine with some additional vibration in the 4-6K range.

Sean

 

[shawn kloker]

crank, rods, counterbalancer (not 100% needed) are in fact the same with few changes. I don't even have a counter balancer in this engine. I probably won't ever do that again but it did work fine with some additional vibration in the 4-6K range.

Sean

I plastigauged mine when I rebuilt it everything was still tight and with in specs.I will be using micrometers next time.

What's turning your water pump without a counter balance shaft?