Blowtie316 Posted November 6, 2014 Author Report Share Posted November 6, 2014 How bout the primary gears? Matched set? Now that I don't know. This engine was assembled when I got it but it came with a box parts that basically is the bottom end minus the cases. They appear to be fairly tight to each other and I don't notice any abnormal wear. I also don't hear any noise when I'm accelerating or decelerating. It is mosly apparent when revving, and the vibration is the same with the clutch removed, so nothing is even touching the primary gear. Quote Link to comment Share on other sites More sharing options...
trickedcarbine Posted November 6, 2014 Report Share Posted November 6, 2014 That rules out the kicker gear as well. How bout the wrist pins? Inner crank bearings? Journal area in the cases where the bearing sits, when they're worn, they tend to let the bearing spin? Gears on the trans shafts are all tight? Quote Link to comment Share on other sites More sharing options...
Blowtie316 Posted November 6, 2014 Author Report Share Posted November 6, 2014 That rules out the kicker gear as well. How bout the wrist pins? Inner crank bearings? Journal area in the cases where the bearing sits, when they're worn, they tend to let the bearing spin? Gears on the trans shafts are all tight? Wrist pin bearings and pistons are new, as is the crank, probably around 4 hours on it and it's vibrated like this since it went together. Everything felt good going together, I am very meticulous when putting it together, I check everything. The bearing journals in the cases looked perfect, no marks from spinning or damage whatsoever. Trans gears and bearings all looked good to me but this is my first banshee so I wouldn't notice everything. It does it with transmission disconnected, so I can only assume it is the crank/rods/pistons area. Quote Link to comment Share on other sites More sharing options...
Blowtie316 Posted November 6, 2014 Author Report Share Posted November 6, 2014 Post a video, focus on areas where you'd be able to see vibration. Right now it's all back apart to check everything out. One of the tension rod dampers was soft so I am replacing the two bottom ones. I still want to put a degree wheel on it and check phase as well as check runout on both sides as well before I put it back together. If it is still vibrating when it goes back together, I will certainly post a video. Quote Link to comment Share on other sites More sharing options...
Blowtie316 Posted November 6, 2014 Author Report Share Posted November 6, 2014 Yeah, the way my buddies bikes are, there is a certain RPM where it peaks, like maybe 4000 rpm (guessing) then after that it smooths out real nice. Mine just gets worse the harder you rev it. The more and more I read, it's probably normal and that is part of the reason that it was rubber mounted in the first place. This thing feels like a cr500. Quote Link to comment Share on other sites More sharing options...
locogato11283 Posted November 6, 2014 Report Share Posted November 6, 2014 Run it. Quote Link to comment Share on other sites More sharing options...
Phelps Posted November 6, 2014 Report Share Posted November 6, 2014 you mentioned spacer plate. are you positive the exhaust isn't hitting something with the elevated exhaust flanges? or possibly the hangers are in a bind causing more transferred harmonics? Quote Link to comment Share on other sites More sharing options...
Blowtie316 Posted November 7, 2014 Author Report Share Posted November 7, 2014 The stingers were rubbing when I first got it, but I have adjusted everything and got them away from the frame, everything looks good now. The only thing unusual is the two pipes themselves basically rub against each other where they turn up behind the bottom of the steering stem. There are flat spots on both pipes like they are meant to sit together. I just got a set of T5s that I am going to try also when I get this thing back together. Quote Link to comment Share on other sites More sharing options...
blowit Posted November 7, 2014 Report Share Posted November 7, 2014 I did not make it through all the posts so my apology if my post is repetitive. You can check runout all day long and not fix a phasing problem!! You can achieve TIR of .0001" and still have a rattle trap if it is not phased right. There are a few ways to check phasing but none are very easy! We build some custom gauging to check and compare the TDC relative to BDC on the other cylinder. However, if you had a vibe, then swapped the crank, and go the same vibes, there might be other issues. This seems sort of complex but last straw but you can pull the side cover, pull the PTO crank gear off and fire it up. If the vibes go away, you have problems relating to the trans or clutch. Still there, the only thing if can be in the crank! Brandon Mull Engineering Quote Link to comment Share on other sites More sharing options...
Blowtie316 Posted November 7, 2014 Author Report Share Posted November 7, 2014 I did not make it through all the posts so my apology if my post is repetitive. You can check runout all day long and not fix a phasing problem!! You can achieve TIR of .0001" and still have a rattle trap if it is not phased right. There are a few ways to check phasing but none are very easy! We build some custom gauging to check and compare the TDC relative to BDC on the other cylinder. However, if you had a vibe, then swapped the crank, and go the same vibes, there might be other issues. This seems sort of complex but last straw but you can pull the side cover, pull the PTO crank gear off and fire it up. If the vibes go away, you have problems relating to the trans or clutch. Still there, the only thing if can be in the crank! Brandon Mull Engineering I will check phase with a timing wheel. I planned to use a piston stop to locate and and align the wheel to tdc on one cylinder, then check it with the other cylinder. Also, I did remove the clutch and gear entirely (started with a drill on the crank nut) and I still had the vibes. Quote Link to comment Share on other sites More sharing options...
blowit Posted November 7, 2014 Report Share Posted November 7, 2014 The timing wheel may find gross phase issues but it won't take much to be an issue! Think your process through or accuracy. IMO, indicators are the best way for this. the $5 ones from Harbor Freight will work just fine!! One of the little tools we made years ago that we still use is used the end off an old comp gauge, drilled the center for an indicator, bring piston up to highest setting, set TDC on wheel to that. works great. Also, that flywheel should be well checked for axial and radial TIR. due to the size and mass, it does not take much to be a big problem. The balance of the flywheel can be tested at any competent engine machine shop that does balancing. Put between centers and test for balance. Quote Link to comment Share on other sites More sharing options...
Blowtie316 Posted November 7, 2014 Author Report Share Posted November 7, 2014 The timing wheel may find gross phase issues but it won't take much to be an issue! Think your process through or accuracy. IMO, indicators are the best way for this. the $5 ones from Harbor Freight will work just fine!! One of the little tools we made years ago that we still use is used the end off an old comp gauge, drilled the center for an indicator, bring piston up to highest setting, set TDC on wheel to that. works great. Also, that flywheel should be well checked for axial and radial TIR. due to the size and mass, it does not take much to be a big problem. The balance of the flywheel can be tested at any competent engine machine shop that does balancing. Put between centers and test for balance. Point taken on the timing. I think it will be accurate to +or – 1°, is there a tolerance for phase alignment? Is the flywheel supposed to be neutral balanced? I had taken a runout reading on the OD of the old flywheel by turning the crank, it was .006" I have not checked the new one. Is it common to have an oem one out of balance? Thanks for your ideas. Quote Link to comment Share on other sites More sharing options...
Blowtie316 Posted November 8, 2014 Author Report Share Posted November 8, 2014 Latest update... I checked runout again on both ends, left side was .002 on the crank, right side was .oo1". Runout on the od of the flywheel with it installed was .006" but it seems to jump around when it gets close to the blocks that pass by the pickup coil so I'm not sure how accurate it is. Checked cylinder bank phase alignment with a dial indicator finding tdc, they were exactly 180 degrees apart. Pressed in a new motor mount bushing on the rear left although there was no real reason for it other than I had already ordered 1, the old one was still fine. Put the motor back in and mounted without the tension rods installed (still waiting on new bushings) and the t5 pipes, still the exact same amount of vibration. I will post again when I get the tension rods installed but I don't expect it to be any different. Quote Link to comment Share on other sites More sharing options...
Phelps Posted November 8, 2014 Report Share Posted November 8, 2014 lets go back to compression. you say 170psi you're borderline alky compression. 180(hot lap/dune)-200 (drag) i would dare to say 113 octane minimum for 170# lets say you're not seeing signs of detonation. ie pitting, shaking plugs out etc there is a slim chance you could still be getting vibrations from pre ignition. simple to solve if it's the case. back the timing down and up it one main jet size. taking away timing/adding fuel will both help cover up deto. i assume you already know this. you seem pretty knowledgeable. it's a simple diag and would love to hear if either helped. maybe a even easier way would to be throw some octane at it. it's imo a good solid rider on lower octane fuel should be around 150psi. Quote Link to comment Share on other sites More sharing options...
Phelps Posted November 8, 2014 Report Share Posted November 8, 2014 kinda reminds me of the oldschool days. motor struggles to turn over from timing being set a little fast. pump the throttle a few times to load the cylinders up (temporarily foul the plugs) to allow engine crank speed to get fast enough that it will start lol the motor may be struggling due to pre ignition. we all know struggle leads to vibration. i know my last blower setup was not struggle friendly. by the time you felt the vibrations you had already melted 8 ground straps and started blasting pistons. Quote Link to comment Share on other sites More sharing options...
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