Partzilla Live Q&A with John Talley – October 22, 2021
John Talley is back for another edition of Partzilla Live Q&A, answering your motorcycle and ATV repair questions.
General motorcycle repair questions and answers for the “big 4” manufacturers were prominent during this week’s session. 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 Highlights – Motorcycle Repair
Yamaha Motorcycle Repair
I have a 2010 Yamaha R1 and the engine blew. It was starved for oil at high RPMs. Could this be an oil pump issue or the oil filter not having enough flow or both?
John Talley: Well more than likely it was an oil flow issue, but let me ask a couple of questions or give you something to think about. I ran into this on an R1 a little bit older than yours. The guy had just wasted his clutch. He just blew it out and didn’t do a good enough job of cleaning it out. He rebuilt his engine and yet it still starved the cams and then chaos ensued and it spun a couple of bearings. It turned out to be there was an oil cooler down on the front side of the engine and it had such small passageways at lower RPMS that you wouldn’t notice it. But at higher RPMs, there was too much back pressure there and not enough flow up top and boom, there goes the engine. So what saved the new build was being very thorough and cleaning every single part of the engine, including that oil cooler, which was the part that brought it to its knees. So be aware of that, especially if you’ve fried your clutch and if the plate’s completely broke down and wiped away, all of that material is still flying around your engine and you’ve got to get it out. So this may have been caused by a not-so-thorough cleaning of the oil passageways.
Kawasaki Motorcycle Repair
I have a 2004 Kawasaki ZX10. I bypass the fuel tank and spray in throttle bodies. The bike will run but not from the tank. Any idea what the problem is?
John Talley: Alright, more than likely, I’m trying to remember, is that fuel injected or not? We’ll answer the question both ways. If it’s fuel injected, it sounds like it’s going to be your fuel pump to me. When you turn on the bike, can you hear the pump prime up? You should hear that click, and then you should hear the motor run for about a second and a half, maybe two seconds, you need to bring up that pressure. If for some reason I’m wrong and this is a carbureted machine, I’d say it’s stopped up somewhere, possibly on the filter on the petcock or coming down into the fuel rail if it’s a carbureted machine. … I think that one is fuel injected, but I can’t remember what year they switched over to that. At any rate, which it is probably an FI bike, it’s more than likely going to be either your fuel filter fuse or the fuel pump itself. And I did walk-throughs on a couple of different machines on how to diagnose that, and one in particular was the GSXR 1000. Although it’s a different manufacturer, the rundown process should be about the same, so take a look at the videos and see if that can guide you in the same direction on your Kawasaki motorcycle.
Honda Motorcycle Repair
My 2002 Honda CRF450 engine is ticking. I changed the cam chain, tensioner, shimmed valves, but the sound is still there. What else should I check?
John Talley: Does that particular model, I know that the 05 has a decompression release or a compression release mechanism on the side of the camshaft. If yours does, that has to be adjusted as well. And I think the total clearance for both of those units is 4 or 5 thousandth. So you’ve got your clamps going to the exhaust valves and then you’ve got that other arm coming off the decompression portion of the camshaft, which should only come into effect at lower RPMs or on startup. But if that is just insanely loose, it may just be sitting there popping back and forth, and that’s what you hear. So check that and see if that’s what it is.
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