jedsled Posted September 10, 2007 Report Posted September 10, 2007 can anyone on here describe how i check to see if my crank needs rebuilding? i have a"knock" in my motor so i was going to tear off the top end regardless. if my crank does need rebuilding, does it really pay to have the crank welded and trued? if i buy a new hot rods crank, does it pay to have it welded and trued? i'm not going to be stroking it, just adding a big bore so is it worth it for me to have it welded and trued for my application? i would appreciate any info anyone can give me on this topic. thanks. Quote
letsgetthisdone Posted September 10, 2007 Report Posted September 10, 2007 get a clymer manual, it'll tell what to check and what the tolerances are. If you need a new crank just buy a new and get it trued and welded. it costs more to rebuild the crank then to just buy a new one... I don't think your crank is messed up though, your top-end might gettin tired and loose and you might be hearing piston slap.. Quote
jedsled Posted September 10, 2007 Author Report Posted September 10, 2007 get a clymer manual, it'll tell what to check and what the tolerances are. If you need a new crank just buy a new and get it trued and welded. it costs more to rebuild the crank then to just buy a new one... I don't think your crank is messed up though, your top-end might gettin tired and loose and you might be hearing piston slap.. ok, thanks a bunch for answering. if it is "piston slap" will i need new connecting rods? or just pistons/ rings/ wrist pins? sorry, i'm new to this... Quote
letsgetthisdone Posted September 10, 2007 Report Posted September 10, 2007 ok, thanks a bunch for answering. if it is "piston slap" will i need new connecting rods? or just pistons/ rings/ wrist pins? sorry, i'm new to this... if your topend is worn you'll just need a piston kit from wiseco, and then have your cylinders bored an dhoned to match the pistons.. If its a good shop, ther'll match one piston to one cylinder and mark it for you, then all you have to do is check ring end gap and throw it together. Get a clymer manual, it'll tell you how to take it apart and put it back together, as well as what your ring end gap should be. it'll also tell you how much play the rod has in it and in which directions that play should be in. Before you order piston and such, you could have a machin shop measure you pistons and cylinders and they can tell you whether or not its time for a fresh topend if they know what the piston to cylinder clearance is supposed to be. If you do need a topend make sure you get the needle bearing for the smallend of the connecting rod, where the wristpins and such goes, they don't come with the piston kits for some reason. And get a complete topend gasket kit. I should've asked this before but....what year is your bike and how many hours do you think are on it? do you know if it has had any rebuilds doneto it in the past? before you take it all apart you can fire it up with the clutch cover and timing cover off so you can better tell where the noize is coming from. Quote
letsgetthisdone Posted September 10, 2007 Report Posted September 10, 2007 oh, and don't go big bore on your stock cylinders. getting a good port job done will net you better gains in power. If you don't feel comfortable takin your motor apart. you can send it out and have a reputable builder tear it down, true/weld the crank (or replace if nessaccary), bore/hone your cylinders, port it, and reassamble. i'll give ya a price breakdown..... true weld crank: $50 ($400 for a new crank that is trued and welded) bore/hone: $90 pistons: $150 port work: $250-$350 depending on what you want coolhead: $235 HD clutch: $100 teardown reassembly: $250 what mods are already on your bike? Quote
Justintoxicated Posted September 11, 2007 Report Posted September 11, 2007 Check the Bearings and see if there is Up/Down play. Check inbetween the Rods with a feeler gauge. I don't rememebr the specs offhand. Check Bearings for other signs of wear. Check where the Crank is pressed togetehr and make sure it is not seperating. Quote
jedsled Posted September 11, 2007 Author Report Posted September 11, 2007 ok, thanks for the good info guys! it is an '89 and it has fatty pipes, boyessen reeds, and fmf mufflers that i know of. its been sitting for 2 yrs. after i had heard the "knocking". i ended up buying a new yfz450 but kept the banshee and want to get it running again! can you guys tell me where can i get a welded crank for 400.00- would it be a new stock crank or something like a hot rods crank? any info is appreciated! Quote
letsgetthisdone Posted September 11, 2007 Report Posted September 11, 2007 ok, thanks for the good info guys! it is an '89 and it has fatty pipes, boyessen reeds, and fmf mufflers that i know of. its been sitting for 2 yrs. after i had heard the "knocking". i ended up buying a new yfz450 but kept the banshee and want to get it running again! can you guys tell me where can i get a welded crank for 400.00- would it be a new stock crank or something like a hot rods crank? any info is appreciated! www.farmandsandtoys.com give jeff a call. he usually has a few trued/welded cranks ready to go. and yes it will be a hot rods crank. Quote
jedsled Posted September 12, 2007 Author Report Posted September 12, 2007 www.farmandsandtoys.comgive jeff a call. he usually has a few trued/welded cranks ready to go. and yes it will be a hot rods crank. ok, thanks "letsgetthisdone", i'll give jeff a call when i'm ready! Quote
jedsled Posted September 12, 2007 Author Report Posted September 12, 2007 are all hotrods banshee cranks trued/ welded straight from hotrods? Quote
letsgetthisdone Posted September 12, 2007 Report Posted September 12, 2007 are all hotrods banshee cranks trued/ welded straight from hotrods? no they're not. they come trued to .003", but i think jeff gets 'em to .001". but they don't come welded. Quote
jedsled Posted September 13, 2007 Author Report Posted September 13, 2007 no they're not. they come trued to .003", but i think jeff gets 'em to .001". but they don't come welded. ok, thanks for helping me out again! Quote
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