34 Tooth Final Drive Pulley?

[1550vt]

I know Wizard and Zook will jump on me if there is already a similar thread out there, but here goes anyway.

I am trashing my JIMS 6-speed (sorry JIMS...can't stand the noise any longer) and replacing it with my stock HD 5-speed. The stock pulley (32-tooth) with my wheel/tire set-up runs around 3250 at 70 in 5th. gear, or around 150 RPM higher than the stock 2-wheeler 5-speed set up. From the math I did, replacing the 32 with a 34 will give me a reduction in RPM by around 6% or 200 or so. I realize it changes the ratio across all 5 gears, but this JIMS had a 3.24 first gear anyway, which I always thought was too tall. Using the 34 should pull that down to around 3. Stock is 2.94. All this would result in a .94 "overdrive" as opposed to the stock 1:1 in 5th.

Has anyone "played" with this 34-tooth change and if so, what results did you achieve? I can't easily change my rear pulley without ripping-out the differential....again and it's a stock 70-tooth.

I have simply had it with any 6-speed and I don't care who makes it. I have ran every fluid except banana peels (old used car salesman trick) in this JIMS and it won't shut-up.

 

[1550vt]

Dave....this thing has gone way past the use of louder pipes. It's a long story, but the short of it is, I bought this trike from a friend of mine. He and I made the conversion back in 01 and he was talked into putting in this 6-speed for better mileage, which never worked out. From day one...it sounded like it had gravel in the case in 6th. gear. He simply parked it for 5-years and I finally bought it. Every other gear was as quite as could be and the thing still shifts smooth as silk, but the noise has gotten progressively worse and when I changed fluid this time...way too much "stuff" came out with the oil for my liking. I trusted it for 34,000 miles, but can't any longer. JIMS said they would rebuild it for $360 plus parts, but it would likely still be noisy. I says...no thanks! Everybody else around here who installed these early JIMS (Baker patent) 6-speeds have long since threw them away, but I hung in there until now.

It has stock primary gearing for the 2000 ULTRA model year and I honestly don't know what that is. I know the pulleys are 32 and 70 teeth. I am looking for a fifth-gear cruise (74-75) of around 3100-3200. Right now I am at 3250-or-so at 70 and around 3400 at 75mph. Stock RPM at 70mph for these year bikes was 3100. I had changed my rear tires to a little smaller aspect ratio and dropped the overall diameter about an inch, which is why I am geared a "tad" too short.

I promise....if you rode this rattling thing around the block...you would park it. My 5-speed is going back in. All I have to do is brush off the dust. It only had around 5,000 miles on it.

 

[1550vt]

Ultraboy....24-tooth drive and 37 tooth clutch. I am not up to speed on what is available for the primary, but it looks like if I just add one tooth there...it will result in about the same difference as adding a 34-tooth output pulley. I don't want to go too far...he!!...I have to be able to take off with the wife, the trailer and all her stuff. But, the good news for me is that I already have a 34-tooth output pulley. It's ALL apart anyhow so I can readily get to either end.

 

[1550vt]

Okay guys....Ultraboy bit on this a little, but let me act real stupid and see if I can get more response. Okay...I don't have to act in this particular case. I have to admit that I have had about every nut-n-bolt loose on this trike EXCEPT the output (transmission) sprocket pulley nut.

I have tried to remove this particular nut (with the proper tool) and I cannot get it to budge. Here is my quandary. I am looking in a 2000/2001 service manual that tells me that nut has left-hand threads and should be turned clockwise to remove it. I have a another set of instructions for a removal tool for 2006 and later models that tells me the nut needs to be removed in a counter clockwise direction.

Does anybody know if HD "changed directions" on the pulley sprocket nut or is one of my instruction sheets wrong? In any event...WHICH WAY DO I TURN THE BLAME THING TO GET IT OFF?

 

[ThirdWheel]

The only thing I can tell you is one of them is correct! Where's the Ultraboy or the Wiz when you need them? I wondering if they are somewhere eating doughnuts.

 

[1550vt]

Never mind guys. It appears that the MOCO threw us another curve somewhere around 2006-7-8-or 9....depending on the model. The later models have right-hand threads on this sprocket nut. Anything 2006 and earlier, should have left-hand threads.

Nope....still ain't got the nut off yet, but from what research I have done....I ain't the only one with nut-problems. I know I have dam! near completely ruined the special tool needed to take it off.

This may require more beer, a grinder to cut the nut off, or some C4 before I'm done, but this nut is not going to whip my arse.

I suppose this has been a one-man thread, but maybe somebody will have the same dumb-arse question I had and find this thread of some assistance.

The "method of choice" seems to be...if all else fails, grind the nut on one of the flats and then break it with a chisel. A replacement nut has to be cheaper than days of labor, special tool destruction and a complete waste of good dynamite!

 

[1550vt]

Thirdwheel....I want to thank you for letting me know somebody is alive out there. For a while, I thought it might be my deodorant!

 

[ThirdWheel]

See I told you one of them was right!! LOL Good luck.

 

[Nauga Mok]

A friend of mine recently replaced the trans pulley on his '08 Ultra with similar luck. Ended up using an air chisel to fracture the nut. Have you tried a little heat yet? If it has locktite on it, heat will help as well givint it a little expantion. Warm it up just enough to make some oil on it smoke & see what happens with a big breaker bar & maybe with some pipe on it. IF you have temp stix, warm it up to 300 - 325. A GOOD impact might be tempting but will probably wreck your special pulley tool, which ain't cheap. My friend didn't have any luck with his impact, but it's not one of the stout ones. He was also using a pipe wrench instead of the right tool. Using a pipe wrench would let it give a little defeating the advantage of the impact like using an extention on an impact does. I wish I had your gearing problem. I need to turn a few more RPMs. At 3,000 at 70 mph, it's just getting far enough up on the cam to quit lugging. 55 - 65 mph is a real pain unless I'm in 4th.

NM

 

[Gorilla]

1550VT sorry was not ignoring you just did not know for sure which way the nut went. I did not want to give you bad info.

 

[1550vt]

Thanks guys. After searching all the forums for a couple of days, I realized that a lot of folks have problems with this sprocket nut, both in removal and direction of rotation.

It just so happens in my particular case here that I have two transmissions, so I can break one if I want to. Actually, I am trying to remove the old drive pulley from the 5th. gear that went in with this JIMS 6-speed I have removed, so no-harm-no foul if I do ruin that seal, bearing or gear. I am throwing it away anyhow and just keeping the case. What I plan to do is get the torch out and heat that nut as hot as I need to get it off and maybe save the nut. I don't care about the gear, bearing, seal, etc. in this transmission case, because it went in with the JIMS 6-speed.

I have this other good 5-speed that I want to put the 34 tooth pulley on and I will grind/chisel the nut off it if I have to, but very carefully, so I don't screw the shaft or gear up. All I want to do is try and recover a "good" nut to go on over the 34-tooth pulley that I want to install on the good 5-speed.

I had to pull my tranny anyway, to heli-coil one of the main tranny-to engine mounting bolts that had been stripped on the assembly line. I found it to be loose one day a year-or-so ago and when I pulled the bolt out, I realized it had been glued back in. That's HD quality for you!

Nauga....yep, I am trying to drop a few RPM in 5th. I had replaced my tires a while back to a smaller diameter to actually re-gear for this JIMS 6-speed, which lugged in 6th. The JIMS blew-up, but 5th. in it was the same ratio as the stock HD 5th. so I knew when I put my 5 speed back in, I would be running around 3400 at 75 and want to pull that down closer to 32-3300.

I have the right tools and a good impact wrench. I hope all this discussion will be useful to anyone thinking about changing that transmission pulley. It's not as simple as it sounds and I now realize the easier route is to do the re-gearing in the primary case. It may cost a bit more for the front sprocket and a chain, but it is not nearly as labor intensive as getting to and removing the transmission output pulley. I just thought that was my easiest route, because I had my transmission out here on the floor anyway.

 

[Nauga Mok]

Another nice thing about changing the gearing in the primary -- don't have to recalibrate the speedometer since the final drive stays the same. I not only need to get the RPMs up in 5th, a lower ratio would help a LOT in getting rollong to start with. The Roadsmith conversion comes out almost dead on with what the 2 wheel speedometer error was. At 75 on the GPS, the speedometer is showing 80, but under 65 it's pretty accurate. I've been thinking about maybe switching to a 6 speed with the same final gearing as the 5 speed to give me a lower low gear. I hate having to slip the clutch under 10 mph in 1st. With my cams it does NOT want to pull much at dead idle without bucking. Pick it up only 250 RPMs & it smooths out, but that puts the speed at between 15 & 20. Does your service manual call for the "torque - turn" method of tightening that nut? When doing that method of tightening, I always put 2 marks on the out side of the socket -- a start point & a end point so when you put the socket on the nut after it's tightened to the initial torque, the first mark lines up with the line on the pulley, marked like it sez in the book. Tighten 'till the second mark at the specified degrees of turn line up with the mark on the pully & you're done. No taking the socket off to see whee you are & putting it back on to turn it another few degrees, take the socket off & check again -- that's a pain!! The major tool suppliers for mechanics -- Snap on, Mac, Matco, Cornwal, etc all now have degree indicators for this method, but I've always found marking the outside of the socket works well & is CHEAP!!

NM

 

[1550vt]

The good thing is that I don't plan to have to do this on a routine basis. I hope this 34 tooth should fix me up the first time. Should reduce my cruising RPM around 200-or-so and that is what I am looking for. I like to cruise around 75-80 and this will pull me down to around 3100, which is close to the stock cruising rpm at 70 with the 5-speed on this model year 2-wheel bike anyway.

Nauga...I am finished with 6-speeds, but I do think there is one out there that offers a gearing at closer to a .97-.98 OD. Mine had an .86 OD, which was too tall for 2-up, trailer pulling, loaded trike riding. To fix my problem (before my 6-speed blew-up), I dropped to a smaller tire with a different aspect ratio and reduced my overall rear wheel diameter by around 1-inch. This made a world of difference. I could cruise in 6th. at around 2900 RPM, which was fine. If you are looking to drop a few RPM, look at tires. You can find tires in just about any combination of aspect ratio to fit your wheel. You can "do the math" and determine how much diameter reduction/increase you may need to get your gearing straight.

I was totally happy with the set-up I had, but when this 6-speed fried...that was the end of it. I know these newer over drive transmissions are suppose to be quieter (so the manufacturers say), but mine was so noisy in 6th. that it became too scary to ride. After I pulled it out, I discovered the trap door bearings were shot. JIMS offered to take it back and re-condition it, but told me there was no guarantee that the noise would be reduced. Never mind...I will just stick with my 5-speed thank you. I never realized any MPG improvement with the 6-speed anyway. You have to have a motor to pull it, and I do have one that will, but still lugged up hills in 6th.

Yes...my manual calls for the tightening sequence you describe.

Look...I know you are also restrained by fender well clearance, ride height, etc. with tires, but if I were you...I'd look at the rear tire size for a gear-change option. It worked for me!

 

[1550vt]

Here is a trick I learned concerning the output pulley removal and installation. I have read all sorts of things people do, like have somebody sit on the bike/trike and hold the brake, open the top cover on the tranny and lock-up two gears....etc. Anything short of purchasing that expensive pulley locking tool.

Well....you can use your Delrin primary sprocket locking tool to both remove and install the output pulley. It will wedge the pulley against the shifter shaft (leave the lever on and put the tool tooth-to-tooth against the pulley) and you can do whatever you want to with it in terms of torque simply by changing the position of the tool.

Yes....you have to slip the belt off the pulley first.