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View Full Version : botched port job...



hawaiianbasshed
08-22-2010, 04:39 PM
ok, so I was thinking my kids bike was running like crap because I torched the crank bearing when I tried to get it off and left it. but now after looking closer at the top end (fresh bore and apparently port) so I looked at it next to the old top end jug and it's clear he did some wanna be porting to it and I'm thinking maybe that and maybe not proper bore/hone to piston specs make it run like crap :confused: any thoughts? should I get some pix of the windows? it looks like a hack job to me now :mad:

LT80
08-22-2010, 07:07 PM
Pics-pics-pics. :)
It does take alot to mess em up tho.

hawaiianbasshed
08-23-2010, 01:20 AM
could be the squish not right too maybe, I dunno. it's .5 over rings look fresh, they were in correct and arrow on piston was facing exhaust... the crank seal had a leak. the base gasket came off in one piece lol so could've been leaking there too I suppose... it was hard to start and would bog easily til ridden for like 2hrs then would finally get to rev out like a 2 stroke.. before being ridden for a long while it was still really boggy... besides the broken case it ran fine til I pulled it apart lol.

I tried to get pix but it was really hard to get. the windows aren't opened larger, the edges are just all flared/beveled in all directions on every opening on the sleeve/jug it looked like... upwards to maybe 3/32"s of a beveled edge lol. the one that was running fine doesn't have anything like that on it... but the one that was running has significant scouring I'm not even sure why it ran, let alone ran good lol. it's at least .75 over as it is larger than the .5 over jug. I'll measure both tomorrow. I was considering boring it up another size but don't wanna waste more money into it at this point. thinking sell cheap so it goes and not look back lol

hawaiianbasshed
08-27-2010, 12:00 AM
eh, wasn't the top end, I changed the crank bearing and the seal looked to be leaking as well as the block where the drunken idiots who worked on it sealed it with high temp gasket maker LOL... so I got it going better now.

one thing I DID notice leaking it looked like, was the reed cage to block... I may seal that with cut out gasket or gasket maker... we'll see. so far it doesn't seem to affect any performance :)

also I noticed the key that holds the variator's roller plate was stripped so the plate that holds the rollers just free spins is that a big concern? it's been like that it looks like. but I did notice it felt like it slips a little today when tuning it, may have always done it but my kid is 60lbs so probably won't slip as much with him riding it. maybe the other variator (couldn't open the old one so I put a different one on that I setup with 3 rollers in) so possibly the rollers are sideways on the old variator I won't know how it's setup til I use my buddies stripped screw remover and look inside... thinkning I can always flip the key so it locks the roller plate so the variator doesn't slip on the shaft lol. I figured the fixed face would help... but then again any excess slipping could/will hinder performance...

I'm just playing with it, trying to get it back to where it was previously, it did wheelies on it's own and now it doesn't so I'm baffled as my milled head added a bit of compression I imagine. and the top end doesn't have scouring the other one was jacked lol. it does spin the tires with me on it, just not as much as I'd expect with the raised compression compared to previously :confused: I'll play with it again tomorrow possibly... stoked to have it running good again.. I need to put a new bearing in the lower steering stem mount at the pitman arm I think it's called..

also my bushings are gone on one of the spindles good hing I have a full spare chassis lol. thinking of getting the spare frame, arms and tie rods and misc parts all powder coated some custom color and keeping the LT80 running as a spare bike as I can't seem to sell it for the life of me on CL for $900 lol. haven't gotten a single email or call lol

LT80
08-27-2010, 06:42 AM
The reed cage shouldn't leak It has a o-ring built into it.
Shaving the head wouldn't do that much. It isn't like you went from 120 to 200 comp. :)

"just free spins is that a big concern?"
Hlel yes it's a big concern. You need a new roller plate now that you've mashed it all together.
3 rollers isn't enough weight.

"drunken idiots who worked on it"...ummm..errrr...LMAO

hawaiianbasshed
08-27-2010, 10:18 AM
mashed? no, the key is stripped not the plate. it doesn't have any key sticking out to strip the plate lol

the other plate was there too, I do realize the entire variator probably spins freely now if the fixed face and belt don't automatically shift it... 3 weights isn't enough? It doesn't have the low end it used to and assumed less weights would help lol. doesn't have top speed like it used to either lmfao. I KNOW that's weights partly at least lol. I'll play with it later :D

hawaiianbasshed
08-28-2010, 06:21 PM
was playing with some of the variators I had laying around, and I ended up noticing the one I put in the rolling pin thing that inserts between the fixed face and variator was only sticking out about 1/2" compared to 3/4" or so on the original variator.. also got a stripped screw remover and the old variator had 3 weights in it as well... so I added 3 more so running 6 again.

I had two spare starter gears w/keys looked in my spare parts bin and found um. but to get the original gear off I had drilled at the key, I banged on it, hit it with my dremel grinder bit and cut out to the key but still couldn't get it off, even after I got it to free spin on the crank lol. just HAD to do all that before drilling holes thru the plate and just using the puller... eh, got one of the older gears on it now with the holes through out it's plate.. hard to say how it pulls on low end it definitely is still close to the same but the top speed seems better by a nice margin. I don't think the belt was going all the way in on the front and out on the rear so low end was comprimised and the weights made the top and where it should be :D

can't wait to get it more dialed in... I have a buddy who's got a few 18x6.5" snow hogs so I'm thinking of getting those and seeing if the little bike has better launch with narrower tires. the 18x9.5"s are more rotating mass so I'd imagine it'll have better off the line :) I'm also running kinda rich it seems like so I'm looking to lean it out on the needle and see how it runs. I have it on the middle clip now with just a UNI pod filter on the carb. but it was bogging previously in the mid rpms and soon as I put it on the middle clip it went away (was on the bottom clip previously) so I'm actually wanting to lean it out even more and see if I can get more of that off the line wheelie power it had before :) just try a few things and see how I can get it going even better. it's almost a mute point since I want to get rid of it anyway. but I figure may as well get it running top shape 1st :D

sorry for the long post, just more tuning going on so I'm stoked every time something actually goes good after all the pita I've had with it lol.