Few Questions about the YFZ?

[raptor_02]

I put the 13/1 piston in and retarded the exaust cam 1 tooth and it ran awesome. But I couldn't get it to start. I was told that I could buy a YZF450 exhaust cam and it would give me the same timing as having my cam retarded and my decompression lever will be in the right spot. Has anyone went with that setup? Also I put 18 inch tires on the rear and 19 inch tires on the front. As soon as I get on the gas I have to shift gears almost as fast as I can until 5th. I'm going to gear it up a tooth on the front sprocket but I was just wondering if your YFZ's seemed geared way to low once you changed your tires. Thanks

[EvilJester400EX]

You definitely want to up your front sprocket one tooth. As for the hard starting, I have heard that by retarding the cam it takes away the automatic decompression release on the engine. However, I may be wrong. Do you think it's your battery? YFZ's do have trouble keeping the batteries at full life.

[trueblue450]

whats your jettting altitude./??? need more info

[Z400central]

hit up www.yfzcentral.com for all your answers. :D

[86350x]

Buy the yz cam, that is the problem.

[JWhite]

You could also try YFZRACER.COM (http://www.yfzracer.com)

They got tons of info.

[biohazard1.2]

Originally posted by EvilJester400EX
You definitely want to up your front sprocket one tooth. As for the hard starting, I have heard that by retarding the cam it takes away the automatic decompression release on the engine. However, I may be wrong. Do you think it's your battery? YFZ's do have trouble keeping the batteries at full life.

The smaller tires and cam mod...up the counter one tooth.

As far as the battery, if always ride with your lights on, you will NEVER have a over-charge related battery problem.

The YFZ bat, along with most other ATV bats are too small and cannot take a sustained charge without some discharge.

The charge-loop provides more charging to the batt than it can handle in a full days ride, without riding with the lights on.

I always ride with the lights on (all of our ATVs) for safety and have not had the "so-called common" battery over-charge.

take care!

oh, the YZ450F cam will put the decomp pin the correct place and will make it substantially easier to start than the stock cam mod.

[big-guy]

The only reason there is even a battery there is to start the engine. That's it. Once the engine is running, the alternator will power everything... you could even take the battery out and it will stay running... if you have overcharging problems, the voltage regulator has issues.

[coryatver]

I don't think it will stay running without a battery. My friends wire came off during a race and it ran for a little bit then would stall out and so he would have to use his hand to touch the wire to the battery and it would run for a little bit and stall again.

If you are all worried about the batterys that have them, and you dont have a need for lights or anything, get that kit for a conversion kick-start that yfzs are supposed to have. It will make it lighter too.. never have to worry about your battery or anything else goin dead again.

[raptor_02]

my battery is fine fellas, i put my exhaust cam back in the correct spot and it starts like a champ. But I've seen all sorts of people with the cam mod and there's starts perfect. My jetting is a 45 pilot, 172 main, and a 90 starter jet. I was told to increase my starter jet with the cam mod and it should start. I'm going to try it later on as soon as I can find a bigger starter jet. I'm at about 1200ft above sea level. I feel my jetting is about perfect for my pilot and main, i think I just need ot increase my starter jet.