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A bit more work on the legshield. There’s no no point in going too far until the frame has been on the jig and any remedial work done.

Well, I’ll get the frame back this week but the remainder of the bodywork is away awaiting splits being welded up. In the meantime, I thought I’d take a look at the top end as, a while back, I had a soft seize. At the time, I put it down to the tank being low on fuel as it cleared up after I’d filled up a few miles further on. That said, for the remainder of the journey home (probably 50 miles, or so) I took it very easily.

On getting home, I checked it over and the standard air filter rubber had developed a split at the bottom by the actual carb. There were no other obvious air leaks. The rubber elbow was replaced and the scooter ran fine after that.

Now, whilst I had the engine out, I decided to take the cylinder off, expecting to find evidence of a seize.

There is no classic sign of a seize although there are some scores on the piston to the left of the gudgeon pin in the photo below. I can only assume that a small foreign body has got in there when I think I had seized. All three ring pegs are still in place.





All cleaned up now.

The only engine modification I did to my standard TV175 was to machine the head to give a sensible squish. I think mine was in excess of 2.5mm so I took it back down to about 1.3mm. I probably need to do a compression calculation before I run the machine as it may now be prone to overheating due to a higher compression.

Leave that one with me.

Knowledge wrote:The only engine modification I did to my standard TV175 was to machine the head to give a sensible squish. I think mine was in excess of 2.5mm so I took it back down to about 1.3mm. I probably need to do a compression calculation before I run the machine as it may now be prone to overheating due to a higher compression.

Leave that one with me.

I have just ordered a 0.1mm aluminium base gasket so, hopefully, I can get the squish down to 2/2.1 now. That’s with no head gasket too. But, the engine was a pleasure to ride before so I am happy to leave the cylinder head as it is.

I hope to have this back on the road in time to, once again, do the Redcar - St Bees C2C on it.

A few hours on the dry build. Work still needed on some gaps and straightness of the runner boards, which is no surprise when you are trying to use the old bodywork.











I popped the bottom bearing track on the forks so I could put the headset on and check that the headset cleared the horn casting. Unfortunately, I never thought to put the bearing shield on. I think this is why there appears to be a large gap above the chrome ring.