Scooterotica

Well IO just typed a 23 paragraph long bit of advice for ServetaKid and bolloxed it off the keyboard while reaching for my 'oj'
SK: here is the 'gist' get it welded locally ( BAR HAVEN, BARROW, WHITEHAVEN) explain it can distort, and it is poss not 'pure' aluminium - they will be used to this bit. Fill ALL 'holes in the case: Mag, studs, mounts where possibe (warn welder about the rubber mounts but say it is essential)

When cool take to competent machinist (BAR HAVEN, BARROW, WHITEHAVEN, CARLISLE, PRESTON, MANCHESTER, LIVERPOOL, GLASGOW) wherever is best to have: Bore milled (76mm or wjatever the spec is?) and planed flat to the original (still visible) gasket surface

Yanker wrote:Well IO just typed a 23 paragraph long bit of advice for ServetaKid and bolloxed it off the keyboard while reaching for my 'oj'
SK: here is the 'gist' get it welded locally ( BAR HAVEN, BARROW, WHITEHAVEN) explain it can distort, and it is poss not 'pure' aluminium - they will be used to this bit. Fill ALL 'holes in the case: Mag, studs, mounts where possibe (warn welder about the rubber mounts but say it is essential)

When cool take to competent machinist (BAR HAVEN, BARROW, WHITEHAVEN, CARLISLE, PRESTON, MANCHESTER, LIVERPOOL, GLASGOW) wherever is best to have: Bore milled (76mm or wjatever the spec is?) and planed flat to the original (still visible) gasket surface

Spanish cases, so wont they be made of a decent alloy?

And what should i look out for inside the bottom end?

I do feel for ya on this one mate, but yea I'd have to agree a standard mec crank on something like a 225? That certainly rings alarm bells with me.

Eden wrote:
aint that a bitch, done it many times. use the preview button now and again when typing a novel, at least then if you loose it you can use the browser back button to get the preview back

Or remove this key (see pic).
Commonly known as the 'highlight all and delete' key.

Muttley McLadd wrote:

IMG_6113.jpg

Or remove this key (see pic).
Commonly known as the 'highlight all and delete' key.

Sorry you've lost me with that one :wtf:

Donnie wrote:I do feel for ya on this one mate, but yea I'd have to agree a standard mec crank on something like a 225? That certainly rings alarm bells with me.

I will be totally honest, i wasnt aware there was more than one type of MEC crank at the time, i only realized after reading more and more post on forums. This was something we had in the house at the time(brand new), so i used it.

If the cranks webs are still OK, you could send them to me and I could take them to Grampian in Crosby to get a decent 110mm Jap conrod fitted, thrust washers, a Jap big end bearing, and balanced. If you're unsure whether the webs are ok, still send them, and I'll ask Grampian their opinion.

You can pay me back some time. No rush. In all honesty, you're probably only looking at £60 to £70.

I agree with what's been said about the casing. A decent engineering shop can sort that for well under £100.

All you need now is for some kind soul to find a barrel that's gathering dust, maybe waiting for a rebore

Paul

Just "eye-balling" the crank in the casing, the webs look further over to the drive side. This might suggest that the CL of the rod big end is not aligned with the CL of the bore. I can see what look like piston shims either side of the SE bearing and not a lot of play either side. Typically the float on the crank is much less than the float on an un-shimmed SE bearing. It could be that shimming the SE bearing has removed all the required float in the big end.

I appreciate you might not have felt any resistance when fitting the barrel to the casing but it really does not take a lot of sideways displacement to put some serious stress on the rod. If stress is there, it will be cycled at engine speed until stress cracks appear then it's Goodnight Vienna. My hunch would be that this is your reason for failure.

Even though Indian crank bearings are pretty suspect the MEC and Italian stuff isn't bad and more importantly a 225 Rapido isn't really going to be pushing the performance envelope and definately not at 55mph after such a short time.

Well SK, you were probably not TOTALLY ill advised and considered 'un-lucky' (get used to it!) to use this crank.

Based on recent personal experience I would avoid the current 'Tameni' crank batches:(no come-back in liikey event of failure) be they Lam GP big-end fails OR Vespa T5 with clutch keyway in the wrong place.....

Your webs are probably OK for a re-build (see prevous post)

Lambreta Love

Richard Taylar sid "I appreciate you might not have felt any resistance when fitting the barrel to the casing but it really does not take a lot of sideways displacement to put some serious stress on the rod. If stress is there, it will be cycled at engine speed until stress cracks appear then it's Goodnight Vienna. My hunch would be that this is your reason for failure."

He expressed what I was bumbling to say

Yanker wrote:
{SNIP}

OR Vespa T5 with clutch keyway in the wrong place.....

Never heard of tameni I have to admit but ive not kept up on a lot of scooter part stuff now for about 4 years, however, I do remember the Mecs with the t5 clutch keyway being in the wrong place back then and bringing it to the attention of mec themselves as well as VE and a few other dealers!

Can't believe it's still happening!