HarleyTechTalk

Well today I had the 79 lowrider out for a short put, when about 15 minutes from the house it decides to rev but not go. So after calling a friend to come get me, I get it home and open up the primary and I am greeted by a primary belt with no teeth. It would appear that someone did a belt drive conversion at some point on this relatively low mileage FXS. But, the belt was a little oily and there was no ventilation in the primary.

Ugh...

If it were me I'd go back to a faithful chain.

I'd be tempted to vent the primary and put a belt back in there 

I converted my 73 Super Glide to primary belt drive. No oil in primary and vented the cover.  After tearing up a couple of Primo belts that used an idler system I switched over to Karata. Years and thousands of mile later no problems. Most all 2 up riding.  Sold the bike o a friend and he ran it until he passed away a few years ago. I can tell you he wasn't easy on it either.

Looks like someone did some clearencing to two of the inner primary cover screw mounting bosses on the bottom of the inner primary. Were the cover mounting screws shortened as well or were none used in those two places?

It appears that shorter primary bolts were used. It took a little time, but I have been able to figure out that this was a Primo 14mm belt drive with a 24-tooth front pulley and a 37-tooth clutch basket. I have never had an issue with 8mm belt drives in the past, but I have only run 3-inch and 2-inch open drives. I was opening this up and was expecting to find a chain, but instead was treated by that mess. So now I get to decide if I am going to clean it all up and replace the belt or put the entire primary drive back to stock with a chain. this was one of the nicer shifting shovels I have owned and it was a piece of cake to find neutral

Quotethis was one of the nicer shifting shovels I have owned and it was a piece of cake to find neutral

 I advocate for a chain but the truth is I've never had a belt drive primary.

  My 76 shifts almost silently since I went to the Rivera Pro Clutch.  To hit neutral at a complete stop I do very slight blip. Sometimes I think that's as much old habit as anything.  It's night and day compared to my 12. 

Well, I got the belt replaced, and while there, I decided to replace the steels and clutch discs. This is probably the easiest 4-speed to find neutral on that I have had with a stock-style clutch. If my previous shovel's clutches were this nice, I probably never would have gone with the RIvera Pro-Clutch on it. 

" But, the belt was a little oily and there was no ventilation in the primary."

That will kill 'em every time. Eliminate the oil, vent and properly align they'll last darn near forever. I Ran primary belts in my Pan and Shovel's for many years. I'm talking road trips from Michigan, to Estes Park, Co. 3 times, Texas, Sturgis 4 times, Tenn. every summer and other destinations. The primary chain? after it left me stranded in Renfro Valley, Ky. I went to the belt and never looked back. 

Indeed, this topic seems to pop up every now and then, and indeed everyone has their own opinion about belt drive. Like oil.
 

DA71FX, I had a very similar incident, except the belt teeth were fine, the belt broke. I tried replacing the belt, but both replacements were tight as hell, could hardly get them on the pulleys. One was so tight it caused the trans to leak, from pulling too tight on the seal I suppose. I finally said what is the point, and converted to chain, no issues since.

I realize many of you have had great luck with belt drive, but consider that Harley-Davidson tried it for a couple-ish years, then abandon it. Wonder why?
 

With the stock belt drive shovelhead models, the four holes at the front of the primary that bolt to the engine are indeed slotted. This is to allow the belt to be adjusted. Since my bike was a conversion, the holes were not slotted, which explains why the belts I tried to install were tight as hell.

And like 76shuvlinoff said, a Rivera Pro (now APM) clutch transforms a 4 speed into a completely different animal. At a stop in neutral, when shifting to first gear, if feels like the shift lever is not connected to anything, makes no noise or hard KLUNK, and seems like it didn't even go into gear at all. But that's not the case, it's just so smooth shifting it's almost unbelievable until you've experienced it for yourself. So no need for me to attempt to convince anybody how great it is. Same with finding neutral, or shifting up/down through the other gears. Definitely the one change I made to my '77 that made the biggest improvement to the riding experience, kicking myself for waiting so long to do it.

-JW

Yeah, but chains don't make that sweet dry clutch chatter that belts do!

Shovelhead uses the same dry clutch for belt or chain. You just don't hear them when the primary is enclosed.

Quote from: Hossamania on May 23, 2024, 04:22:10 PMYeah, but chains don't make that sweet dry clutch chatter that belts do!

Sure they do, just don't use any oil in the primary and run the chain real loose.
 

And true Ohio, same clutch (unless you change it). But my primary with the belt was very well vented, and it made quite a chatter. Ducati-class (satan's sleigh bells), no, but not too far from it (more like Santa's elves sleigh bells).

-JW

Quote from: Deye76 on May 23, 2024, 06:37:50 AM" But, the belt was a little oily and there was no ventilation in the primary."

That will kill 'em every time. Eliminate the oil, vent and properly align they'll last darn near forever. I Ran primary belts in my Pan and Shovel's for many years. I'm talking road trips from Michigan, to Estes Park, Co. 3 times, Texas, Sturgis 4 times, Tenn. every summer and other destinations. The primary chain? after it left me stranded in Renfro Valley, Ky. I went to the belt and never looked back. 

I went the opposite way.  When a stone flew up off the road and broke a belt (Primo) "again"    as I was road testing before a long trip, I put the chain and compensator sprocket back on my 56 slabside stroker.  After I put the primary cover back on I never looked back either.  The double row #60 chain (even though it broke once and piled up in the back of the primary skidding the rear wheel at the car's driver's door as I was passing a car on the highway    it was available at any farm supply.  Living where I do I preferred the availability offered over ordering a replacement from California when on a trip.

And you're right Hoss.  That jingle song the plates sing is very cowboy macho.  I ran my crank case vent to there and my rear sprocket.

" it was available at any farm supply. "
I doubt that it was the same chain. I too found some on the road at a tractor/farm supply, it was low speed machine chain, lasted about 800 miles.

Quote from: Deye76 on May 24, 2024, 04:58:27 AM" it was available at any farm supply. "
I doubt that it was the same chain. I too found some on the road at a tractor/farm supply, it was low speed machine chain, lasted about 800 miles.

Oh it definitely wasn't the same quality chain but it was almost as available as a cup of coffee to go.  That's why everyone had full and half link master links with them.   Mine did last longer than 800 miles though (except for that one time I had that pucker experience passing the car).   

Ha-ha, KD! The pucker factor must have been tremendous (basing that on my sudden rear tire deflation while passing a car late one evening riding solo (and in a hurry) to Halifax.
Sometimes ya meet the nicest people from those situations - well, here ya do at least.

"We're all A-holes. It's to what degree that makes us different."

Well thank you for that Tacocaster! Now I get to clean the coffee off my screen and keyboard!
 

But indeed the funniest and wisest words I've seen all week!

-JW