dajogejr Posted November 19, 2010 Report Share Posted November 19, 2010 Did he buy the cheap crank or the more expensive crank from TDR? Over on ATVDragracers.com, this is a DIRECT QUOTE from Tony Dukas himself. Hey Guys. The crank parts are imported and them assembled in the US. All the components are Taiwan made and seem to be holding up fairly well so far. If you are an abusive rider, over-rev especially I would always suggest the better crankshaft. We are stocking them to be able to be competitive with all the other vendors. We still have all the higher quality cranks and parts in stock as well. I have also been updating my website daily with a lot of new items. If you have more questions on the cranks or any parts just contact me. Thanks Guys Tony Doukas Quote Link to comment Share on other sites More sharing options...
BigRed350x Posted November 19, 2010 Report Share Posted November 19, 2010 I'll stick with Twister. All made in the USA. Louie is great to work with. Let us know how that TDR crank works out in there... Quote Link to comment Share on other sites More sharing options...
shanYE west Posted November 20, 2010 Report Share Posted November 20, 2010 I'll stick with Twister. All made in the USA. Louie is great to work with. Let us know how that TDR crank works out in there... I've seen my fair share of twister cranks fail also. I'm not saying any crank is better then another.. but.. It all starts with installation.. if it gets stuck in a crap set of cases.. crank could be made of gold and its still gonna fail. Quote Link to comment Share on other sites More sharing options...
stroking Posted November 20, 2010 Author Report Share Posted November 20, 2010 HE got the $800 TDR 10mil Quote Link to comment Share on other sites More sharing options...
BigRed350x Posted November 20, 2010 Report Share Posted November 20, 2010 I've seen my fair share of twister cranks fail also. I'm not saying any crank is better then another.. but.. It all starts with installation.. if it gets stuck in a crap set of cases.. crank could be made of gold and its still gonna fail. Very true... I just try and buy American made stuff whenever I can. Quote Link to comment Share on other sites More sharing options...
shanYE west Posted November 20, 2010 Report Share Posted November 20, 2010 Very true... I just try and buy American made stuff whenever I can. Very True.. lol Quote Link to comment Share on other sites More sharing options...
makemefaster Posted November 22, 2010 Report Share Posted November 22, 2010 That vitos 4mill i bought from a kid on here looked exactly like yours does. I took it to a local builder thinking it was just junk he trued it and re-welded it said that it would be fine that the motor it came out of was the problem not the crank! He said almost word for word what dajogejr said. Must be some truth to it. I havent had a chance to run it yet so i dont know what it will do. It will be tested though i am running a set of bubba297s welded ported drag cuyl on alky! Quote Link to comment Share on other sites More sharing options...
J-Madd Posted November 22, 2010 Report Share Posted November 22, 2010 I've seen my fair share of twister cranks fail also. I'm not saying any crank is better then another.. but.. It all starts with installation.. if it gets stuck in a crap set of cases.. crank could be made of gold and its still gonna fail. The properties of gold would make it unsuitable for a crankshaft. The melting point is way too low, and its too soft of a metal. Quote Link to comment Share on other sites More sharing options...
camatv Posted November 28, 2010 Report Share Posted November 28, 2010 TDR cranks are solid. the cheaper WSM ones he's offering i dont know.. ALWAYS RUN TZ bearings you cheap asses!! picks above for sure show why. that crank also looks to wide like the center is not pressed all the way together right,, just had a BRAND NEW wiseco that was that way welds look like total shit sent it to crankworks to be rewelded and pressed and set up corectelly,, the banshee manuals have the measurements for the crank and you can measure them even before you install them.. that pin has NO penetration at all. Quote Link to comment Share on other sites More sharing options...
TDR_50 Posted January 20, 2011 Report Share Posted January 20, 2011 Hey Guys . I am not on the forums very much as I am always busy. I have seen thousands of crank failures over the years. Every different type of failure has a specific sign as to what happened. If you have multiple failures and the same type of failed parts something is being missed. In diagnosing a crankshaft failure I look at the evidence, (what has failed), and work backwards to find the problem. I started rebuilding crankshafts in 1973 and to this day have rebuilt, (my company & workers) close to 50,000 crankshafts. All 2 strokes and a very small amount of 4 strokes. Right crank bearing outer race failure: The cases are matched sets and CAN NOT BE MIXED . They are line bored from the factory. If you mix cases you will have bearing failure. Bearing clearance is by spec clearance scale. If the crankcase area where the bearing ride is out of round by even a few 10,000 of an inch it will put pressure on the outer race and this pressure will create friction in the ball or roller area. This friction will create heat that will further close the clearance resulting in catastrophic bearing failure shown in some of the previous pictures. Once a bearing fails or spins in the race the crankcase race is generally out of spec and cases are now trashed. Crank separation. Crank web separation has a few different causes. First, pin to web clearance is critical. The interference fit or press fit needs to be within spec. If it is excessive or too tight the web will crack and the material will roll and distort. This results in never being able to true correctly. If it is too loose it will separate. It is up to the crankshaft assembler to be aware of the amount of pressure being applied on assembly. Once a crankshaft has been assembled with the correct pressure and it separates there as other reasons for that failure. Over-rev: Over-reving is another reason for crank separation. An engine makes horsepower at a specific RPM peak and looses horsepower beyond that. A CPI exhaust has a power peak at 9800 rpm. We have installed data acquisition on many motors. Ones that are prone to crankshaft failure are ones that are continually over-revved. Over-revving creates a harmonic vibration that shows up in different ways. One is crank separation, Crankcase bearing surface chattering marks, flywheel separation, lower rod bearing cage failure. Over-revving cases a large percent of the failures followed by improper installation or not being aware of any crankcase imperfections. Also keep in mind you are revving the engine at the start and dropping the clutch. The tires try to stop the engine or crankshaft rotation on the right side while the heavy flywheel is still moving on the left side. Crankshaft twist applies here. Also press fit also applies in this case. The looser the press fit the faster the crank will twist. This twisting creates pressure again on the bearing race and creates heat and eventually failure. There are 2 different lower rod bearing cage styles used in most of the Banshee cranks. The more expensive cranks use the better bearing. Again over-revving will cause the lower cage to break apart and the small pieces will be evident in the top of the pistons. The small pieces will contact the rollers and make them skid causing lower rod meltdown. Out of balance flywheel and welding of the flywheel onto the crank web. If a flywheel is pried on to remove it the flywheel shell will be out of alignment with the inner solid support. The only way to remove a flywheel is to use the correct puller that pulls directly in the center. Any prying or tapping on the outer shell will cause damage. This misalignment will again cause a vibration and make the crankshaft separate and chatter. Misaligned flywheel key: When installing a flywheel key you must make sure it is seated correctly or the flywheel will be off-center and cause the same separation and vibration. Offset keyways are especially prone to this. I do prefer a good adjustable timing plate. OIL: Outboard motor oil is not a high-performance oil. Not that you have taken your 33 horsepower from the factory Banshee motor and are producing more that 100 hp the same oil does not sufficiently lubricate the critical parts. Especially if you are using alcohol. Alcohol is a solvent. Solvents dissolve and wash down oil from the moving parts. Special oils are required for alcohol engines. If this oil is not used the crankshaft moving parts will fail quickly. Lack of lubrication is evident when the disassembled parts are inspected for excessive wear or general meltdown of the lower rod parts. And I can keep going. The crankshaft leads a very hard life and needs proper assembly and proper oil to run a long time. Even if installed perfect with all new parts, over-revving and rider mis-use will destroy it in only a few runs. Just because a crankshaft fails it is not necessarily the crankshafts fault. All 3 components combined, proper build, proper oil, and proper rider input, will result in a long running motor. If this is not your case carefully read the above. Quote Link to comment Share on other sites More sharing options...
camatv Posted January 20, 2011 Report Share Posted January 20, 2011 nice to see you here tony! my 10 mill TDR has benn the most reliable crank i have ever had. 5+ years of 535cc dune abuse. Quote Link to comment Share on other sites More sharing options...
dajogejr Posted January 20, 2011 Report Share Posted January 20, 2011 Nice Post Tony. Quote Link to comment Share on other sites More sharing options...
stroking Posted January 21, 2011 Author Report Share Posted January 21, 2011 i notice that the crank seal on the clutch side is installed with the smooth side against the bearing,could is cause a bearing to fail ? shouldn't the humps on the seal be facing the bearing? Quote Link to comment Share on other sites More sharing options...
sheerider1026 Posted January 21, 2011 Report Share Posted January 21, 2011 i would think the seal is designedthat way to let the oil make its way into the bearing.. but good eye.. it definately backwards Quote Link to comment Share on other sites More sharing options...
rjatv Posted January 21, 2011 Report Share Posted January 21, 2011 I am no expert but thats deff backwards, it could be one of the problems for sure. Quote Link to comment Share on other sites More sharing options...
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