Here TK, see that rusty barrel? But two containers of Evaporust,empty into a large container in a fashion to submerge the barrel in the Evaporust and leave it for a few days. When you remove it,there will be no rust left.
I filled a crank case on a rust seized crank from a CT1 motor and it unseized it much to my total amazement. 
you can recycle the Evaporust after as well.
Dave

A puzzling one. I never saw the like before. Took the barrel to work and stuck it in the hot wash to degrease it prior to blasting it.

Took it out and gave it a look over to make sure all the oil and grease was gone.

In the upper fins at the rear was what looked like a honeycomb or wasps nest. Only instead of being made of paper, it appeared to have been constructed of a very hard clay like material.

The hot wash made no impression on it. A new one on me. Any ideas, it being a US bike?

Anyway, barrel was checked for taper and oval (fine), blasted and then given a quick hone for new rings. Just needs paint.

Clutch steel driven plates were stuck in the derust bath and then given a quick turn on the linishing belt. They are useable, but not great. Quite a bit of micro pitting on one of them, but still straight. I should replace it but nah, it will work ok. The rest were not as bad as they looked.  Basically after derust, they were just water marked and most of that came off after linishing.  I have had to refit worse in long out of production trannies.

New Vesrah frictions have been ordered.

New Koyo mains have been ordered.

Found a new genuine yamaha piston at a bargain price. Actually it was the only standard one I could find advertised in the country. It cost about the same as a chingaling cheapo piston.
I guess the bike shop thought it being std size, it would not be in demand.

Circlips and small end ordered. Already have genuine rings in stock as well as a full gasket kit.

Head is going into work tomorrow for a dunk in the paint remover bath and the clutch pressure plate is having a turn on my bench grinder wire wheel.

Apart from the oil pump seal kit and the airfilter, I think that is engine complete.

If everything turns up, I will build it and fit it on saturday morning. Might even have it started this weekend..

Perhaps a mud dauber wasp?  Depending on the mud used they can be very tough.  Fairly common around here. 

Mud dauber? I don't think we have those in the UK. I never heard of one.

What part of the US are they in? Might give a clue as to where the bike hailed from.

I've seen them in the Southwest...  I have no idea of where else they might be located. 

We have some of the sorts from the bee world up here in Mn, USA… any kind of hole, pipe or hollow of sorts get their attention… Usually have to pick away at their handy work with a nail or something to that effect..
pesky bugs..
Sneezles61

We have them in The southeast we call them dirt dauber’s nest some are made with clay 

I think the mud dauber wasp originated in my pole barn here in Michigan. I've lost count of how many times they've caused me grief. Like the time they plugged the water outlet on my 15 HP Evinrude outboard motor.

By the sound of it I am glad the cells were open and empty.  They sound fearsome.

US critters seem more pesky than UK ones.  From watching vice grip garage ect, it seems that within weeks of parking a vehicle up in the US, a family of mice have built a nest in the airbox and eaten all the insulation off the wires.

I have heard of it happening in the UK, but it is quite rare.  I have never witnessed it myself.

Mind you, one distressing mouse habit in the UK is to get into the loft, bite into the ring main wiring, get zapped by 240v, catch fire and burn the house down.

 

Dirt daubers don’t usually don’t sting humans. We have mice that will chew wiring on autos I know they chewed the wiring on my wife’s F150 glad it was a easy fix they say it’s the new insulation that attracts them also Vice Grip Garage is about 4 hrs from where I live.