Results 1–30 of 118
this is very reliant on having accurate marks. take lots of care to ensure you are properly marking each degree in relation to tdc. having a mark is useless if you dont know what it correlates to.
this is interesting. im going to install an athena kit on my motor. i felt the piston was very loose in the bore, so i mic'ed it at work. my particular kit has over 5 thousandths clearance. way out of spec for what it should be. i mic'ed a poliini today and it was 1.2 thou (slightly tight, perhaps the reason people seize them?) im seriously considering experimenting with knurling the pis
you should run the lowest octane you can in ANY combusion engine without detonation. the higher the octane, the harder to burn. in a low compression this results in an incomplete burn and equivalent if not worse performance. if you really want to run it and see an improvement mill the piss out of your cylinder head until you get a compression ratio of about 16-1 and then youll have a fun ride. oth
you and i are the same way it seems :) ive got a new msd coil for my engine for my car id try if it were 6v. i personally have no problem paying 40 bux for something thatll work well
bitter, id really like to hear if you have a way to source a new coil like the one you speak of. since you think so highly of it id like to put it on my new project and do some experimenting. any hints on where to get one and specifically whick is needed?
you need a coil for a magneto ignition. those are designed to be used with either factory ignition or a msd box. there is zero need for them as there are mopeds hitting 70 with stock ignitions. unless you plan on building a 16+ to 1 comp motor with methanol as fuel, your time is better spent learning to port or other tricks of the trade. take the time it would take you to convert that coil you cou
if you dont rebalance the crank, be prepared to replace your crank bearings at much shorter intervals. there is a lot more precision to doing that PROPERLY than just finding something to "fill the holes"
paz ftmfw! DEATH TO FLAT HEADS!!! dont sell my set :)
havent read the jennings article, but from what i know, ring flutter is caused by a buildup of compression pressure between the top and 2nd ring, which causes the pressure on the top ring to equalize so it can flutter. solution for this on high performance car engines is to gap the 2nd ring the same or larger than the top. dunno if jennings mentioned another cause of ring flutter, but that wouldnt
i just dont bother clicking those posts.
4 stroking is almost always even sounding. you are probably detonating, which will sound more random. theres zero reason for your motor to be doing what you think its doing unless you got some really funky cable action going on
i installed a wilwood 4 piston brake kit on my mustang. their solution for accounting for casting variations of the spindle: washers.
knurl is the raggedy sharp file-like edge on bike pegs and other metal bars for traction. when applied to a piston skirt, it raises the surface, essentially increasing the bore size the piston fits. weve got a machine to do it on auto pistons, what weve got is much too big for a moped piston but i bet theres a knurler out there that would work.
babooze, i work at a machine shop. we would waste hundreds of dollars a month if we just randomly ordered pistons without knowing what overbore we are going to need on the block. the final size is dependent on the damage caused to the cylinder. the machine shop will tell him how far they need to take it. if its beyond the largest overbore, then theres no saving it, unless they can knurl the piston
any engine machine shop can probably do it on their rod hone. ask them to do it before you order the piston so they can tell you what size they had do finish the cylinder at.
sawed off 12ga would work well. cant think of much else
compression = powercombustion engine basics.just because its harder for you to turn over by hand doesnt mean its harder for the motor.
its all mechanical so on paper its possible. what you need to do to be truely accurate is come up with another equation to figure what amount of torque is required to pull each gear, then create a hp/weight chart to correspond to your gearing forumla. i expect it in a week or so :-D
i run one. if the number doesnt help, you need a cross over vent tube filter. youll be able to find them at a circle track or sprint/midget performance site i had to get a little creative with some radiator hose, but it worked out well
maybe it was a car website? the choke horn on a 4 barrel is a flow restrictor in high flow/rpm situations and they are removed from high performance carbs. thats got zero to do with 2 stroke though
if it doesnt clear, go to auto parts store and get prebent radiator or heater hose with a size and bend appropriate to move the filter where it will work
possibly a rusty tank. fill a bottle with gas and ziptie it to the ped to test, see if its still orange
itll move side to side, you need to pull upwards on it (like into the cylinder head) to check for play. it should have none. if it moves forward and back when you pull on it, the crank needs to be replaced.
thats interesting to know k&r. im a newb when it comes to cycles, as i just got my first recently. ill keep that in mind for future motorcycle work
torque values relate to the strength of given hardware and the amount of force they can take. the size, material and thread pitch determine the particular value for each bolt in any given condition (wet, dry, graphite). ive built over 100 car engines, and have yet to ever see a torque value for a main stud or rod bolt given dry. i did your google search and found more than 1 post about someone say
all torque values are meant to be measured with some sort of lubricant, be it oil or high pressure lube. torqueing somehting dry usually results in binding of the metal and incorrect torque specs. not exactly a super big huge issue at 30 lbs on small studs, but that is in fact the proper way to torque something. cant get a good reading if the metal is trying to bite the threads.
you can try cleaning it, using a rust inhibitor and cold weld from the parts store. better thing to do is find someone who can tig it up. drop it by a body shop and see what they think, since you didnt post any pics
its junk, ill take it off your hands for 5 bux:-Dseriously tho, ill pay you good money for it if you decide you cant use it.
your cylinder wont rust as fast because its got lubricant on it from the oil. however letting it sit in that state will definitely hurt it eventually. long and short of it is your not fucked, just dry it off enough so you dont hydrolock or hurt the mag and run her to dry the rest.