Mate, try any of the vendors that sponsor this forum for piston/jug assy, u'll probably get it as a rebuild kit. U'll also need a complete gasket set, including crankcase gasket, pistonbikes or just about any of the others, plus the 2 crank seals. The main & countershaft bearings are 6202's & they're common, just get quality. They'll likely be sealed, leave as they are for the countershaft, remove the seals & wash the lubricant out for the crank. Replace the outter seals only if u want, not the inner. Someone has posted a link for a high quality small end bearing. I dont know wot ur big end is like, hopefully its ok. CheersCan these motors take the extra power?
- Thread starter Rocky_Motor
- Start date
Yepper that's what i am tiring to figure away to separate the crank measure the pin. then get it back togather the right way. I have a 5 piece, 6 screw crank, and a 3 piece, alignment seems the key issue
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any Ideals?
. any Ideals?
hi mate, if ur measuring the pin I take it u split the crank. Its gotta be indexed when putting back together, (not a "home" job) & trued. U should also balance to 57 percent/reciprocating weight while ur there. Take any material from the inside of the two bolt on weights replace all fasteners with automotive grade socket head items. have fun, cheers
I think they can tbh. As long as you stay on top of maintenance usually things are pretty sweet.
Its usually when ya get lazy they will catch you off guard.
Id always carry gasket goop, crankseals, spark plug, magneto, and tools on the long hauls to work and back every day. The backpack was usually half full of bits and pieces to pull me through just about anything.
Id basically go to and from work as fast as I could every day, roughly a 40min ride each way. Bike had every mod. I could be bothered with on it.
Way I see it is the motor is just making more power thru the efficiency of the mods.
If you got less mods usually you would punish it harder to try and get up that hill better or whatever. If the motor has more power up its sleeve and your just cruising I reckon thats gotta be better.
Once you get up to speed you can just role off the throttle and cruise along rather than holding it pinned all the time coz its gutless to keep it at that reasonable speed that is quick enough.
if your really relying on these bikes though its handy to either have a spare motor you can just drop in sitting at home or better yet a spare bike sitting there ready to go.
Its usually when ya get lazy they will catch you off guard.
Id always carry gasket goop, crankseals, spark plug, magneto, and tools on the long hauls to work and back every day. The backpack was usually half full of bits and pieces to pull me through just about anything.
Id basically go to and from work as fast as I could every day, roughly a 40min ride each way. Bike had every mod. I could be bothered with on it.
Way I see it is the motor is just making more power thru the efficiency of the mods.
If you got less mods usually you would punish it harder to try and get up that hill better or whatever. If the motor has more power up its sleeve and your just cruising I reckon thats gotta be better.
Once you get up to speed you can just role off the throttle and cruise along rather than holding it pinned all the time coz its gutless to keep it at that reasonable speed that is quick enough.
if your really relying on these bikes though its handy to either have a spare motor you can just drop in sitting at home or better yet a spare bike sitting there ready to go.
Are you sure your crank isn't a little bent.
If the shaft coming out isn't turning 100% true and has abit of a wobble about it you will chew seals like no other. PITA when this happens.
Easiest way to check is pull your spark plug out, take your magnet off the shaft, remove the magneto and now tie your bike up with rope in the air or if ya can just flip it upsidedown when theres no fuel in it.
Its usually easier to just flip you bike up side down so you can really hone in on a good view of that crankshaft.
Disengage the clutch and turn the motor over via your pedals and keep a close eye on that crank shaft coming thru the seal... I'll put money on it the damn thing is oscilating. Let us know how ya go if ya end up checkin it out.
The seals on these things can be quite good. Some motors can last for ages without replacing them so long as they are getting lubricated well enough even with all the super hard core mods.
Although I never needed to use one I have a couple seal retainer plates, holds over the top of the seal so it won't back out, screwed down under the mag winding.
mate, if, when u replace the crank bearings, u leave the outer seals on the new bearings, u wont have the problem with the seal popping due to increased crankcase compression ratio. As u said, the magneto seal, which is only 3.5mm wide is popping from stuffing the cases, not leaking from a bent crank. The outter seal, if left on the bearings will take the brunt (so to speak) of ur increased compression ratio. Cheers
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if u do leave the outter seals on the bearings, wet the other seals with oil (this should always b done anyway) as they wont be getting lubed from mixture. They shouldnt need any more down the track, tho u could add a little periodically if u like. Cheers
Just order the last 10x14x15mm pin I could find, http://www.spmotostore.com/HIGH_QUALITY_NEEDLE_BEARING_p/s6-802002_xl.htm is were I got it. 29.91 bearing shipping and handling
Good bearing mate. When u compare the fit of the 10x14x15 in the piston/rod assy to that of the OEM bearing u'll c how much better it supports the piston at extremes of bearing side drift. The OEM is like, half out of the rod. The piston bosses r way 2 far apart. U'd think 1 of the performance parts manufactures would do a properly designed piston with the bosses spaced no more than 14mm apart. We'd all want 1. Chheers
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Thanks for the tip I go through like water gonna pay a little more attention to crank end play also, now I need better 202's you mentioned a Japanese product?
Look What I was playing with....http://iwitness.weather.com/_Out-my-front-door/video/1715649/148597.html
Look What I was playing with....http://iwitness.weather.com/_Out-my-front-door/video/1715649/148597.html
The 6202's I used r NTN, rated for 20,000 rpm.. They're available on Rock Solid Engines web page, tho I got them thru bearing supplies, about $15 each I think I paid, but I think I got a discount coz I know the guy, but I'm down under mate so,,,. SKF is good, but u can get them in different RPM ratings, no matter wot brand u choose, u'll just have to do ur homework 2 find wot u want. Google them.
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Lightster361, u split ur crank, hey, so u'll need a shop to put it 2gether. Its gotta b indexed (so the 2 halves r in the right position in relation 2 each other). While ur at it, u should balance the crank to suit the rev range u intend to be using. U balance to a percentage of the total reciprocating weight. Low 50's for moderate rpm's, like 52 or 53 percent, & higher 50's for higher rpm, like 57 percent. Cheers
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Also, if ur gunna b riding in the wet u should epoxy seal ur magneto stator (coil). Under a vacuum if u can, so the epoxy gets right thru the windings. Its pretty easy 2 do & works brilliantly. Water wont ever b a problem 4 u again, at least with this aspect of ur electricals. Anyway, I've forgotten where we're up to & I need another drink,,, cheersIvan, the reason that none of the high performance manufacturers have made pistons is because they don't have a foundry. All they got is mills and lathes. High silicon aluminum is a b*tch to machine, and that is what is required for pistons. Piston manufacturers want to use as little machining as possible because that grade aluminum eats lathe tooling. In a few years, my backyard foundry might be capable of making pistons. I will be making intake manifolds this summer, don't know who I will sell them through yet. Possibly high compression squish band heads, too, if I can buy a lathe this summer. More likely next summer. Anyway, first prototype manifold will be done early June, latest. I would love to see good pistons but not likely until I can make my own.
