A year ago I traded my 08 RK at a HD dealer. Sometime later I ran into the new owner of my old RK. I bought the RK with 20k miles on it from a HD dealer. It was a repo but in great shape. During the 18K miles I owned it, I changed the tranny fluid 3 times using Mobil 1 75w90. I never detected a problem, even the day before I traded bikes. Also, I never towed a trailer and rarely rode 2 up. When I did the fluid changes, there were never any shavings.

After the new owner put about 2k more miles on it he said while cruising in 5th gear, that it would sometimes slip into 4th gear on it's own.

Lucky for him, he bought an extended warranty. The HD dealer told him that 3,4,5th gears were toast. I asked him if they elaborated on that diagnoses. He said "no".

I have many theories. One is, the dealer exaggerating/fabricating the damage because the warranty insurance is paying for it? He was told the rebuild was costing $4000. Two, maybe he caused the damage? He is somewhat new to street bikes and this is his first Harley.

During the 2 years that I owned it, the fluid was changed and I periodically checked the level and it never leaked.

Aren't these trannys tough? They don't get hot like an engine does and are not exposed to outside contaminants. Don't most tranny outlast the engine?

I'm just looking for some input. I have a 2014 now and I am using Mobil 1 and changing it every 7k miles. I didn't buy the extended warranty and I hope I don't have to look forward to a tranny rebuild at 40k miles.

 

Kinda thinking the same thing as you regarding the dealer thing. Either that or the new owner liked to power shift without using the clutch. Good timing on your part though.

 

Door bearings are retained with snap rings which are insufficient in handling the axial thrust caused by the helical cut gears. Because the snap rings allow the shafts to move it puts an additional side load on the main drive gear and bearing. The main bearing is a double row bearing with two separate races. The inner race the thinner of the 2 takes the brunt of the load heats up and melts the plastic bearing cage. Then your ***** in the bearing are free to roam around. Nasty business. The mainshaft has 4 gears as an integral part of the shaft and weighs 6 pounds, far to heavy. The overall stack up on some 6 speed gear sets are far to loose and cause a rattle in neutral and **** poor shift quality.Oh and finding neutral with these loose stack ups is like trying to find a virgin at a 40 and over party.

Are these enough reasons or should I continue.

 

Thank you Mark. Very good points. But don't most Harley trannys make it past 40k miles before failure? I do realize that most Harley never see 40k miles but a lot of the touring bikes go way past that mark.

 

The 5 speed transmissions yes, 100K plus no problem. The 6 speed Harley transmission, some get lucky, some don't. I've seen them fail at 30K, beef up the motor and throw some additional torque at it and good luck.

 

My 6 speed made it 130,000 miles but badly needed bearings! I think I got a Wednesday tranny. Always shifted great and easy to find neutral. Now if someone cold make a decent main gear drive bearing it would be a solid unit...

 

I was able to get 55k out my stock 5 spd but the motor was not stock. had problems grabbing second and third. under real hard accelerations at high rpm's it wouldn't shift to second or third..... If I baby'ed it it would shift.... They're not bullet proof. Not sure if any tranny is... If you baby it and perform proper maintenance it will last a long time , if you ride hard it won't........