TOPIC:

I've just got back from another test ride on the 1970 98 Seigiorni.

I couldn't get the OEM Dellorto ME18BS to run anything but ridiculously rich at idle. I suspect the float is allowing too high a fuel level in the chamber but a new on is nearly £40 with P&P plus VAT.

So after seeing mention of someone in the USA successfully running a 106SS on a Chinese Keihin PZ pit bike copy I decided to try one. A new carb, pod filter and even a twistgrip and cable for half the price of a dellorto float. It needed modifying to fit after removing the Gilera intake stub, but it works very well. Idle mixture is pretty good at 1 1/2 turns out of the air screw and it now needs choke to start when cold. The standard main jet it came with prove a little small at 68 but a swap to a size 80 allows it to pull wide throttle under heavy load now. Possibly needs to go another size or two larger for optimum results but now I've changed the float chamber screws for socket head screws a main jet change doesn't require the carb to be removed. I suppose I ought to have another try with the Dellorto, but it was running so rich it was sooting up the plug to the point of not sparking.

The custom small end bush I had made and fitted myself seems so be holding up. The used cylinder and piston but rings from the piston it came with work OK, though compression is a bit down I think. However, it has stopped smoking! Turns out I must have sloshed a couple of litres of 2T mix meant for the KTM in when I first got it home by mistake. Once I filled the tank to the brim with fresh petrol the smoke abated completely

It is even slower than I expected though, at least up hills and so I can't see me keeping it long term. It will reach 55mph downhill but I don't like HGVs breathing down my neck if I stray on to national speed limit A roads.

I'll take it to a few very local VMCC events over the summer and then probably sell it on to someone with the time and patience to do a full restoration. Though as a 1970 it may not really be worth it. Then I'll look round for an early 60's 175. This will be financed by selling the KTM as it's not being used now, as I don't get on with it and the lad is likely to be living away from home permanently once he graduates in June. Anyone in the market for a KTM250EXC two stroke Enduro/Supermoto fun weekend bike?

Hi

Preaching to the converted

But "Good on you" for taking the time to put all that information and your story on the Forum.

Thank You

We need to try to rekindle things a bit or we will be lost

Cheers

ZacPike.