KaN Powersports Posted November 10, 2013 Report Share Posted November 10, 2013 Using piston stop method (I modified a sparkplug with a long bolt through it's center) and a degree wheel, set up for TDC on one cylinder, not bumping the wheel or pointer at all! Set up the piston stop in the other cylinder and rotate the engine around, and referring to 180 on the wheel compare the phasing (120 for triples). There are tons of forum info, and youtube info on using a degree wheel. For those of you who have never used a degree wheel-but it is very simple and accurate. Piston stop method eliminates any play variables in the engine assembly (bearings and what-not).... You don't even have to tear down your engine for this proceedure, other than removing the flywheel. Quote Link to comment Share on other sites More sharing options...
apeik Posted November 13, 2013 Author Report Share Posted November 13, 2013 So, got it torn down, stator side crank seal one lip is completly smooth(even though it didnt lose pressure). Big end bearings on old crank are loose...to the point you can twist the rod and it over 3mm of small end play. My question is, is this just from running lean, or did the crank have alot to do with this piston sieze/smear. Both pistons with maybe a little more than an hour runtime if i had to guess, have a sieze type looking mark up the front left exhause corner of the piston, the side that backed the plug out once is the one in the picture. Brand new nikasil, and brand new pistons. Also there was some blowby on the transfer sides right past rings, on both pistons which is a first. Quote Link to comment Share on other sites More sharing options...
KaN Powersports Posted November 13, 2013 Report Share Posted November 13, 2013 Show us the crown. What's the wall clearance? I'm still blaming untrue crank with all current info... including bearing wear. Pics of wrist pins too... Quote Link to comment Share on other sites More sharing options...
apeik Posted November 13, 2013 Author Report Share Posted November 13, 2013 (edited) this is a video link of big end bearing play Pto side is a tz bearing btw. Edited November 13, 2013 by apeik Quote Link to comment Share on other sites More sharing options...
apeik Posted November 13, 2013 Author Report Share Posted November 13, 2013 (edited) forgot pics of the wristpins, ill get them up in a bit, they dont look to out of the ordinary though. This crank was like this when i got it as well.... Ready to Run and tight.... Edited November 13, 2013 by apeik Quote Link to comment Share on other sites More sharing options...
apeik Posted November 13, 2013 Author Report Share Posted November 13, 2013 Here's a pic of the wristpins, if you look closely you can see lines going lengthwise down the wristpins where the wristpin bearing runs...and you can ever so slightly hang a nail on one or two of the marks. These were obviously new with the pistons with less than 2 hours...these looks worse than the one's that backed the plugs out 5+ times last time it was together, which i dont think had any of these marks. I would think crazy detonation...but the left plug was backed out once, about 4 turns with these wristpins in. Quote Link to comment Share on other sites More sharing options...
KaN Powersports Posted November 13, 2013 Report Share Posted November 13, 2013 There it is!! If you are running the stock primary/clutch combo, then the crank got walked by the helical gears!! To run a TZ correctly you need a C-clipped bearing, and straight cut gears.... Do you have straight cut gears? or the stock primary? Quote Link to comment Share on other sites More sharing options...
KaN Powersports Posted November 13, 2013 Report Share Posted November 13, 2013 OK, I just watched the video clip-TZ's are the roller styled bearing, and MAXLOAD are the ones with more balls in them. Is it a TZ? Plus the rest of the play is no good.... If it is a TZ, it could very easily be the culprit for the slop everywhere too... "Edit" Watched the vid a second time, it's obvious it is a TZ-haha. Is your new crank coming with regular bearings? Quote Link to comment Share on other sites More sharing options...
KaN Powersports Posted November 13, 2013 Report Share Posted November 13, 2013 I don't doubt one bit you were into DET also, but the seizing is a result of the "crank-walk" IMO... That crank was a bad ordeal from the get-go and you didn't stand a chance with it... 7 degrees out of phase, loose bearings, TZ with no locating clip on another bearing elsewhere, and I'll bet it's runout is off the charts too... Quote Link to comment Share on other sites More sharing options...
apeik Posted November 13, 2013 Author Report Share Posted November 13, 2013 yes, new one's is coming with normal bearings, and it's definetly a TZ roller bearing. I asked jim from passion if i should run it before i every put this motor together the first time...and he said it would be fine, that's how the guy i bought it from was running it. i knew it wasnt right with helicial cut gears though... Quote Link to comment Share on other sites More sharing options...
apeik Posted November 14, 2013 Author Report Share Posted November 14, 2013 should also note that the primary gears were lined up..at least sitting still...is there a chance under high rpm/power it was actually pulling the whole assembly over and then relaxing and moving back over? the whole crank is a pile of crap so i guess it doesnt really matter at this point...i shouldnt be to suprised since i knew going in the crank was less then optimal with loose bearing's everywhere...just didnt have the 400 to replace it at the time, since i had so much going to just make it work with pipes/carbs/pingle and all the other stuff you generally need. Quote Link to comment Share on other sites More sharing options...
KaN Powersports Posted November 14, 2013 Report Share Posted November 14, 2013 That's exactly what happens inside there; Because of the helical gears you get side walking. 1-The TZ allows more side movement (for obvious reasons) 2-When you take the stock bearing off and add the TZ you do away with the crank's only locating clip. To do it right you need to machine a clip groove elsewhere in the case and move the locating clip. I have done my own before with the 'pinned' polaris NTN bearings and dowell pin holes drilled into the case as an alternative to the c-clip. Either way, you HAVE to re-secure the endplay of the crank somehow. And the straight-cut gear minimizes this side loading. However, you still need the locating clip. Quote Link to comment Share on other sites More sharing options...
trickedcarbine Posted November 14, 2013 Report Share Posted November 14, 2013 I am actually in your same shoes Apeik. I couldn't get mine to fire and went through the electrical over and over. Bike just wouldn't fire or throw spark when it should've. So I actually tore the whole thing down begging for backwards pistons or something stupid. Sure enough the crank was way out of phase and cracked welds. No more work from the local shop or Weisco cranks Quote Link to comment Share on other sites More sharing options...
apeik Posted November 14, 2013 Author Report Share Posted November 14, 2013 Well, let's hope both of our problems are solved, ive been fighting retarded overheating and detonation for a long time hopefully because of this crank...there's really nothing else it could be unless my cdi went bad..but would just not advance at all and run bad i would think. Incidentally ive read alot of threads about crank reviews and whatnot in the last week or two, every thread i could find in fact, and it's to bad about the wiseco cranks, back in 2003-2007 only thing you heard was rave reviews of them being bulletproof...then they turned to junk after that..according to old threads. I actually decided to step away from hot rods for once because ive read some good reviews on the new vito's 4 mil LR crank...let's hope it pans out, im just tired of going out and not being able to ride over and over, has wasted alot of money just to keep it parked in camp. Quote Link to comment Share on other sites More sharing options...
KaN Powersports Posted November 14, 2013 Report Share Posted November 14, 2013 Wiseco's are now purchased from inland China, and (I'm not sure) I suspect they hail from the same place as the Wang Crank-Black webs, Funny rods, and substandard bearings-junk in a box. Wisecos used to be Hot Rods a while ago-not any more... I build all of my cranks (including my strokers) I'm in control of quality and assembly pride that way.... Quote Link to comment Share on other sites More sharing options...
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