Partzilla Live Q&A with John Talley – April 10, 2020
Partzilla’s resident master technician John Talley found himself stuck at home due to the coronavirus quarantine, so one Friday he decided to host a live Q&A session.
Due to the positive response to that first session, John will continue doing Live Q&A sessions every Friday at 3pm Eastern. John answered a variety of questions about motorcycles and ATVs, and even gave pointers about how to become a master mechanic. Check out some ATV highlights from John Talley’s first live Q&A, and tune into our YouTube and Facebook channels every Friday at 3pm EST for the next live sit-down with Mr. Talley himself!
Partzilla Live Q&A Highlights - ATVs
Got an ‘02 Honda 400EX that has a tick coming from the top. I check the timing chain, it’s very tight. I check the valves and they’re right. What else could it be?
John Talley: I’m a little bit concerned about the timing chain being so tight. It should have just a little bit of play on it … And I would say go back and make sure you that you actually have your timing marks correct when you’re checking the clearance because what you’re describing really sounds like a valve clearance issue.
My 2014 Polaris Sportsman 850 XP has oil in the airbox. What should I do?
John Talley: The first thing I would want to check is if it’s overfilled with oil. Because it’s spitting oil through your breather tube into the airbox … where it expels excessive gas buildup inside of the engine itself, when you have blow-by. Something else you may need to check if your oil level is correct is to do a leakdown test, make sure that you don’t have damaged rings and that’s making way too much pressure go past the piston and into the crankcase and expelling out through your vent into the airbox. So hopefully, you just have a little too much oil in there and it’s not the latter, which is going to require a new set of pistons and rings to be installed.
Hey John, on the Raptor 700 build I didn’t notice you checking the cylinder to case depth. Is that something I have to worry about with new cases?
John Talley: It’s not something I’ve ever had to deal with before. When we order the factory parts OEM, you usually don’t have to do that. Now if you were going with a big bore kit, and it was made outside of the manufacturer’s system, some kits do that. I would definitely check it at that point because you don’t know what tolerances those base plates, or the base of the cylinder were actually built to. So at that point, yes you need to check. If it’s OEM, there’s no need to, you can just go ahead and bolt it straight down as I did on that particular video.
What would you recommend for someone that is looking to buy a used 4-wheeler? Are there videos about this on your YouTube channel?
John Talley: I believe that we did, I remember recording one and actually, it was more geared toward buying anything used … what I would look for if I were walking into what I would call a “Craigslist offering” to make sure you have a chance of getting a decent unit.
Want to see more live repair questions answered? See John's April 17, 2020 Live Q&A session below, or watch all of John’s Live Q&A sessions here.