Hi guys I'm new in this forum and also a new zilla owner, recently bought 2 zillas 87 and 89, I'm going to restore the 89 first but I have some doubts about what accessories should I buy, PTR Power Head or Pro Design Cool Head? is it possible to choose different domes for the PTR? If Cool head is better which dome should I use, 57, 59 or 62cc (pump gas)? Keihin 39PWK or 41PWK?I understand that the 41 is a bored 39 not a original Keihin model, is this right? which Clutch kit would you recommend?
I would be very grateful if you could help me with this restoration.
I have heard that even the cool head needs the dome reshaped. Personally, I would send the stock head out to a good builder to have it cut and o ringed for your riding style and fuel.
Welcome to the HQ. Just one question. Are you missing a cylinder head or are you wanting to replace your cylinder head? Either way, the head needs to be machined to correct the quench band.
If I'm not mistaken, Pro Design makes the cool head for PTR so they are the same. The size of the dome will be one of the determining factors of your compression ratio. Your compression ratio is one of your determining factors of your fuel octane requirements. And pump gas does not fill the requirements. You are gonna need at minimum, 100 octane race gas for a zilla.
I would steer away from the PWK carburetors and use a Mikuni TM-38. This can be bored out to a 41 if need be.
As for clutches, Barnett is probably one of the best.
I ran pump gas in many zilla engines without issues... They all don't need race gas.
As for the carb, I have ran a pwk38, tm48 and a vm44 on a zilla. They are all good. Just need to make sure you use the correct jets, mikuni jets in a mikuni carb and keihin jets in a keihin carb. Don't use shitty jet kits like the dyno stage 2 or something. I personally like the pwk carbs because I have more experience with them on more quads that just the zilla.
If you want to try something new, there is the smart carb. Some people have been saying they work well on single cylinder engines. They are just not cheap.
For the head, just get a pro design and have someone that understands the zilla motor to cut you a dome. You can order blank domes and have a builder machine you a custom dome to match your engine setup and fuel.
I ran pump gas in many zilla engines without issues... They all don't need race gas.
As for the carb, I have ran a pwk38, tm48 and a vm44 on a zilla. They are all good. Just need to make sure you use the correct jets, mikuni jets in a mikuni carb and keihin jets in a keihin carb. Don't use shitty jet kits like the dyno stage 2 or something. I personally like the pwk carbs because I have more experience with them on more quads that just the zilla.
If you want to try something new, there is the smart carb. Some people have been saying they work well on single cylinder engines. They are just not cheap.
For the head, just get a pro design and have someone that understands the zilla motor to cut you a dome. You can order blank domes and have a builder machine you a custom dome to match your engine setup and fuel.
From personal experience the smart carb doesn't work well on the big single cylinder set ups.
Most I have seen with luck is the 250cc crowd, like the trx and dirt bikes.
There is a guy that had luck with a banshee, but the others didn't.
I ran pump gas in many zilla engines without issues... They all don't need race gas.
As for the carb, I have ran a pwk38, tm48 and a vm44 on a zilla. They are all good. Just need to make sure you use the correct jets, mikuni jets in a mikuni carb and keihin jets in a keihin carb. Don't use shitty jet kits like the dyno stage 2 or something. I personally like the pwk carbs because I have more experience with them on more quads that just the zilla.
If you want to try something new, there is the smart carb. Some people have been saying they work well on single cylinder engines. They are just not cheap.
For the head, just get a pro design and have someone that understands the zilla motor to cut you a dome. You can order blank domes and have a builder machine you a custom dome to match your engine setup and fuel.
From personal experience the smart carb doesn't work well on the big single cylinder set ups.
This has been my experience also.
Some of my customers that have installed the smart carbs say they run better than the carbs they took off. When I ride their bike, I am not impressed. The carb that they took off must have run really bad.