Two Stroke Gear Box Oils

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To all: do any of you run the HDEO's in two stroke dirt bikes that have the gear boxes separated in the own oil? Was wondering if the high priced motorcycle gear box oils (75W, 80W, 85W) have any benefit. This is probably a repeated topic, but I would appreciate any feedback. Thanks.
 

PT1

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 Originally Posted By: mikeyoilnutt
To all: do any of you run the HDEO's in two stroke dirt bikes that have the gear boxes separated in the own oil? Was wondering if the high priced motorcycle gear box oils (75W, 80W, 85W) have any benefit. This is probably a repeated topic, but I would appreciate any feedback. Thanks.
Most guys I know just run a GL5 dino 75w90
 
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 Originally Posted By: wileyE
atf or motor oil, wouldn't use use hypoid gear oil like gl5
why motor oil but not a gear oil? I've read about several people using ATF with no reported issues.
 
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GL5 is for ring and pinion gears like in rwd rear end. It usually not the best stuff for clutches. Drags when cold and slips when hot. twostroke gearboxes run pretty cool compared to a fourstroke, so the oils stays a little thicker. Atf or a non energy conserving 10w30 has always worked well for me.
 
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i ran Pennsoil type F ATF for years in my yz250 (smoker) tranny. never wore out the clutch and it was shiney clean every time i took it apart. changed it before every race or 2 practices. back then it was $1.49qt
 
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I've ran atf in a 2 stroke and I didnt care for it long term. I never did a UoA on it, but I've heared from those who have, there's a tremendous amount of metal created versus a heavier oil. I see I'm in the minority >G<
 
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The manuals for my old Yamaha RDs recommend 30 weight engine oil. That's 35 year old information. As much as I like HDEOs, I prefer to run a gear lube in these old machines. I run Bel Ray Gearsaver. Probably more for peace of mind than practical reasons.
 
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I've had very good luck with the Motul semi-synth oil crankcase oil in my roadrace bike (Aprilia RS250). Good level of clutch friction and shifts have stayed snickety-snick. But I swap after every race weekend. -ted
 
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I would never run ATF in a two-stroke gearbox UNLESS it was a new vehicle and that was the REQUIRED lube for that specific application. On my three Kawasaki Triples (750 cc H2, 500cc H1 and 250cc S1) I once tried a GL4 gear oil but didn't like the way it shifted untill it was very hot. Hotter than it would usually get in normal riding. The absolute BEST! shifting and cluth action was with AMSOIL (I believe it was the "regular" version, i.e. AMO) 10W-40 Synthetic. Cheers!
 
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Ford ATF works very well in two stroke MX gear boxes. There are many gear oils marketed (like Castrol MTX) that are little more than 10w30 oils. My favorite oil for my KX125 was Redline Shockproof Light. After 40 hours of racing, I would normally be replacing clutch plates from heat/glaze. I inspected, and measured. All the plates were still at spec, and not blued from heat. They went back in. That is great stuff. I have 4 quarts of Phillips 66 Racing gearbox lube from Dr.Redszus at Precision Automotive Research http://precisionautoresearch.com/ left over. I'd be willing to sell them if you were interested. I never got to try the product, but it is supposed to be high quality stuff for two stroke MX, separate boxes like HD, and manual transmissions . PM me if you want to give it a whirl.
 
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beanoil, that sounds great. I was thinking of the super-light Shockproof oils ... but Red Line products don't always preform as well in the real world as they do on paper. Gald to hear this worked out for you. With all the excellent manual transmission fluids available, I'm surprised no one here has tried the following: Royal Purple Syncromax (ATF thin with better add-pack) Pennzoil Syncromesh (or the equivalent Chrysler/GM OEM fluids) Red Line MTL Amsoil MTF Nissan 75W-85 MTF Any or all of the above may be an ideal compromise between traditional 90 weight gear oils and motor oils or ATFs which simply don't have the add-pack for gearbox protection. For all-out racing, the super-thin Royal Purple product seems to be a no-brainer.
 
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Many of the mtf's specifically state "not for wet clutches" in their product data. Amsoil and penzoil for example. The additive for the sycro's would most likely be the problem.
 
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OK wileyE, that makes sense. Thanks. But then it does open-up a niche some specialty lube manufacturer could exploit. Offer a 8.0 - 10.0 cSt lube specifically for dirtbike gearboxes ... with the proper add-pack and coefficient of friction. :)
 
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