Engine Identification & problems

[ripzay]

Hi Guys

As some of you are aware, i blew my engine up a couple of weeks back.

I bought another engine, fitted it, and i hate it, i have a combination of issues that are making it a pain to ride rather than a joy.

The Situation:
- New Engine
- Old Engine's Carbs
- Old Engine's Clutch (the one that came with the new engine was buggered so i put my clutch out of my old engine in)
- Old Engine's Front Sprocket

The Problems:
- It bogs down in first, this is a combination of two things i think... let me explain...

The first gear on this new engine is MUCH MUCH longer than the first gear on my old engine, which makes me think it came off an SP bike, but i'm not sure. (Is there any way to find out based on the engine number?)

There is a fuelling setup issue, but i havent pinned that down to any one thing yet...
When i blew my engine up it showered the third carb with bits of metal filings, which i stripped and cleaned out, i'm thinking one of them may have damaged the diaphragm. other options are my choke is sticking on on one or more cylinders (because i've had the carbs out, i might have knocked the choke slider off a plunger by accident)

Any ideas guys ?

just to note - the carbs are set up exactly as they were on my old engine, except i've rebuilt number 3, when they were on my old engine it ran fine, just needed balancing.

Also - is the jetting different on an SP engine ?

Thanks!

Ben.