Partzilla Live Q&A with John Talley – June 18, 2021

John Talley returns for another Friday edition of Partzilla Live Q&A, answering your real-time motorcycle and ATV repair questions.

ATV repair ruled once more, and John got a great variety of questions related to what could be considered “The Big 4” (Honda, Kawasaki, Polaris and Yamaha) of quad manufacturers. Check out some excerpts from Partzilla’s latest live Q&A session below, and tune into our YouTube and Facebook channels every Friday at 3pm Eastern for the next edition. 

Partzilla Live Q&A 06-18-21

Partzilla Live Q&A Highlights – ATV Repair Questions

Honda ATV Repair

Can a rectifier cause a weak spark in a 99 Honda 400EX?

John Talley: Probably not, because the rectifier is in charge of making sure you’ve got the appropriate voltage going throughout your machine. Now could that actually cause a weak spark? That’s a long shot, but that’s going to be an easy way to find out. Go ahead and put a voltmeter on it when you’re running it and see if you’re getting somewhere north of 13 ½ volts while the engine is on a little bit of a fast idle, let’s say 2000 RPMs. And maybe max out around 14, 14 ½. And if you’re getting that type of voltage then it’s not going to be a weak spark. More than likely it’s going to be the coil itself going bad, so that would be the first place I would look. Make sure you’ve got the appropriate voltage, and then maybe take a look at that coil, especially if it starts to degrade as the machine heats up. …

Kawasaki ATV Repair

I picked up a Kawasaki KFX 700 and it needs some maintenance. Are the brakes or the rear diff fluid change hard to do? 

John Talley: We have yet to do a video on that machine, but I can tell you from my experience with Kawasaki that it shouldn’t be that tough to do at all. And although the fill level and the torque values are going to be different on that particular model, you can at least look and see how to go through the procedure on a multitude of our videos, and the one closest to that is probably going to be our Yamaha Grizzly, that would probably be the best one to look at … 

Polaris ATV Repair

I’m going to be buying a 1998 Polaris Sportsman 500 4x4 tomorrow for $2,900. It’s brand new with less than 1,000 hours. Is this a good buy?

John Talley: Brand new with less than 1,000 hours? Wow. I guess your definition of “brand new” is a little different than mine. One thousand hours is a pretty good bit of time on a machine. It really is, especially on an ATV. 1998, $2,900? I’m not a NADA encyclopedia or a Kelley Blue Book expert, but it kind of sounds high to me. What I would do if I were you is to go to one of those two websites, plug in the information for the unit and see what the fair market value is. And they even break it down per area, but off the top of my head I think that sounds a little high. 

Yamaha ATV Repair

What oil should I use in a Yamaha YFZ450 sports quad, brand new rebuilt?

John Talley: Well, that’s a double-edged question. If you’re telling me that you just rebuilt the engine, you need to go through a break-in procedure and to do that, I would recommend just using a standard, regular oil. You may want to add in an additive so it’ll harden up in there like it’s supposed to … go through that initial break-in procedure, which is only going to last about an hour or an hour and a half … I believe we also did a video that explains my opinion of the break-in procedures, whether it be sport or utility or a street bike, you may want to go find that in our library and listen to what I have to say. But after you finish that initial break-in, I would definitely go with that semi-synthetic for the YFZ450. That’s what I did on ours.

Want to see more live repair questions answered? See all of Partzilla’s Live Q&A sessions here.  


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