Catastrophic Engine Failure - What Are my options?

[Doom Patrol]

Newly rebuilt? Fifty five miles an hour uphill? Do you not know the meaning of restraint?

You know Scootopia are doing Indian 200 barrels and pistons for £32.00.

[servetakid]

Newly rebuilt? Fifty five miles an hour uphill? Do you not know the meaning of restraint?

You know Scootopia are doing Indian 200 barrels and pistons for £32.00.

The piston and barrel were already run in, so was crank, so was bearings. Just had the engine apart and put a taller sprocket in, new chain, new clutch corks, fresh oil and a slight tune. I did 50-60 miles of slow-ish riding, seemed fine and up jetted as the plug was a tad light. Dont see what i did wrong?

[Yanker]

I'd agree with the previous comments: Case worth repair, rest not: except if the crank webs, big end eye, taper and threads are undamaged, than worth considering re-building that with a quality rod kit eg Yamaha, MB or BGM.

As for the cause: further investigation required but big end seize, small end seize (those shims!?), or major failure/lock-up in the transmission/drive train. Also as a precaution check clearance of the piston skirt to Mag at BDC (some of the Mag transfer area looks 'proud' to me in the pics eg a small block Mag un-modified?)

Crank build and rod kit, new top-end, crank bearings, case weld and mill. about £500 worth + your time.

Genuinely sorry to see it happen to you! Identifying the cause may avoid a repetition and also help others. Pls keep us posted on what you find?

[servetakid]

I'd agree with the previous comments: Case worth repair, rest not: except if the crank webs, big end eye, taper and threads are undamaged, than worth considering re-building that with a quality rod kit eg Yamaha, MB or BGM.

As for the cause: further investigation required but big end seize, small end seize (those shims!?), or major failure/lock-up in the transmission/drive train. Also as a precaution check clearance of the piston skirt to Mag at BDC (some of the Mag transfer area looks 'proud' to me in the pics eg a small block Mag un-modified?)

Crank build and rod kit, new top-end, crank bearings, case weld and mill. about £500 worth + your time.

Genuinely sorry to see it happen to you! Identifying the cause may avoid a repetition and also help others. Pls keep us posted on what you find?

The small end if fine, the piston was free. Cant tell with the big end as the rod is jammed in between the webs and really bent. It looks intact with lots of oil on the bearing!

I did about 4000 miles on it last year and alot of full throttle riding. I spent hours setting the squish last year, and was within the tolerances. Definitely no piston contact on the mag housing or head.

[servetakid]

it could also be that the wrong tool/method was used to hold the crank when undoing the front sprocket, or at some previous time, if you used say a socket extension in the p155 it would have put a lot of strain on the little end end of the rod, it could have even broke it leaving just a bit holding it together.

I cant remember TBH, think i may have used a clutch holding tool.

[servetakid]

I have done it before, but was doing clutch so had the tool about. I cant remember the minor details but it all seemed to go fairly smoothly...

[Yanker]

You pulled the chain case cover yet?

That crank was certainly 'under-spec' for the job IMHO.

Strip the engine carefully (taking note of tell-tail signs). It will all come good in the end!

Ok and don't forget to report

[servetakid]

What am i looking for when i take the chaincase side off? The engine turns over and ironically, it still sparks...

Yes, the crank is to blame i guess. And maybe the little extra power from the mild tune sent it over the edge. (sticky will say i told you so soon )

Still open to suggestions on where to repair the cases?

[goldeneye]

go and buy a load of drink and a bag of dope, and play some good music. think about it tomorrow.

[servetakid]

I did that yesterday (minus the dope) hence why I'm asking today....