1982 XC250 Questions

Hello fellow left kickers. I have a 82 XC250 that I am restoring and looking forward to riding real soon. I have a couple questions for you all and hope you can lead me in the right direction:
1. Does anyone know the stock length (number of links) in a stock chain?
2. Has anyone tried a Keihin flat slide carb on a Husky engine, I am looking for performance and not worried about being class legal as we ride our own series here in the Northwest. Not sure if it would fit?
3. Are there any aftermarket exhaust pipes that really add performance and not just looks. I know Vintage Iron makes one has anyone tried one?

This is my first Husky and it has been a lot of fun getting it back together.
Thanks,
Mike

Carb and pipe questions

I have a 38 mm flat slide Keinin from a KTM 300 exc parts bike if you're interested. I have two Husky 430's with the 38mm Mikuni like yours. The Keinin measurements are OD on intake manifold end = 45mm; OD on airbox side = 63mm; overall width from intake side to airbox side = 90mm. I was too lazy to take one of the Mikuni's off and measure it for comparison.

LHill

The measurements would probably fit, the manifold end would be a little tight but it might stretch. The stock mikuni is about 30mm longer due to the large intake bell they used. I also have a 300XC-W and might take it apart this weekend to try and see if the Kiehin would fit. The later 300's come with a 36mm that really helps the low end. I will let you know if it does.
Mike

I'm running a 38mm PWK on my 81 430 XC. It fit right into the stock intake and air filter boots. Looks cool, too! Mine's from a KTM.

Here's a PWK on my 81 430. Air filter boot fit fine, also. Bike starts and runs great, but I haven't finalized jetting yet.

The PWK carb is a great addition and better set up than the Mikuni. I am glad Picklito has done all the hard work with the fitting. I have a 36mm Kiehin PWK on my KTM 300 and it is so easy to jet. I actually used a JD jetting kit and it was spot on for the KTM. This might be something I will try in the future along with a Mossbarger reed valve. Has anyone tried one of these reed valves? They claim to flow up to 30% more air/fuel and I know Team Husky used them back in the day. More flow= more go.
Mike