The sand would have embedded into the alloy, hence all the scoring. The pistons would have been away from the engine alright but should never have been blasted. The whole engine and all its parts will need many washes to make sure all the grit is gone. It is a recently built engine and just look at all those vertical scores on pistons and bores. Fascinating to see how someone can do so much damage during a rebuild.I’ll change all the bearings while I’m there anyway. I would have thought even the daftest person would have sandblasted the pistons out of the bike and cleaned them. The other bore is in good condition so hopefully that’s not the problem but we’ll see. This could be getting expensive.
Conrods need to be checked for roundness on the big ends with the shells removed and the nuts snugged. If there's no slop in them, they're PROBABLY good. No need to replace if they round at the bottom and have no nicks or deep scratches.Well hopefully I’ll do it it right this time. On a side note are Conrods usually changed on a rebuild. I’m presuming they are the original ones. And what’s required for the cylinder head.
I’ve ordered the clutch tools see if I can get round the pinion puller when I’ve split the cases. It’s fingers crossed at the moment just have to see what I’m dealing with.I was thinking of loaning the engine tools but too far away. That pinion puller is very expensive and possibly not use it again for many years. Clutch tool and clutch locking tool is something you will often use. The small end bushes can be removed with something you make up easily.
I have never had to replace con rods on a bike just used on the road sensibly. Not even had to replace valve guides on any bike i have owned long term. Just check it all as you take it apart.
next surprise could be the crank journals if sand blasting grit has got in.
There's not a square inch of free worktop down at Mick's place. Goodies everywhere.Where are you in the UK, I’ve got lots of stove enamelled barrels with mostly new pistons sitting on the shelf - ask Alex The Biker!
If you are over this way, I can get that plug out in minutes in my fly press, but don’t even think about bringing it on the back of the bike!There's not a square inch of free worktop down at Mick's place. Goodies everywhere.
Unfortunately, Mick, I stripped that ultra-seized and mega-rusty T140 to the very last but one bolt; never managed to get sludge-trap cap off, can't hold crank from moving. It's in boxes upstairs.
Still, lovely cylinders!
I always replace the rods with the superb billet connecting rods made by Thunder engineering.Well hopefully I’ll do it it right this time. On a side note are Conrods usually changed on a rebuild. I’m presuming they are the original ones. And what’s required for the cylinder head.
Hi Gpz,Good stuff, but WAY over the top for a typical classic bike that won't be thrashed constantly.