Norvil belt drive conversion

Thanks Ken.

In the picture that Hobot has posted with the Maney outrigger, what is the item directly below the swinging arm bolted with 4 bolts to the cradle?

willy mac said:

In the picture that Hobot has posted with the Maney outrigger, what is the item directly below the swinging arm bolted with 4 bolts to the cradle?

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Pay no attention to that, it's just Hobots rump rod :shock:

(mount point for a lower rear link rod)

numerous learned folks have told me that loose is best. The belt should almost touch the top of the inner chain case when you lift it. remember that the gearbox adjustment also changes the final chain drive tension. Belts are a really nice way to lighten the bike, reduce chain car leaks and give the drive system some needed flex.

Essentially in all belt applications the tension is set on what feels like the loose side by allowing for fairly easy full 90' twist in longest mid run. This also means the gear box can be welded in the cradle as belt should be loose enough to work on and off w/o any adjusting to slacken further. Ideally one looks up the pulley diameters and the belt tooth count and looks in charts to find the ideal center to center tension distance, so tension ends up as above. This is how top fueler belt driven everything drag bikes belts tensions are set, from the foot long fuel pump to the 10 ft long final drive and all the thick and thin ones in between. Nothing needs venting in our applications, so holes are for showing off mass reduction artwork. If you can sense clutch wobble then your new belt may not stay new very long.

This is the best explanation I've ever read about setting up a belt drive. It's written by Kenny Cummings. It is written like a journal without page numbers. **** May 2010 – Back to Spannerland **** is where he covers the belt. You'll wind up reading it from start to finish though, it's a great read.

http://nycnorton.com/2010/01/racer-2010/

Like Bill said, check the tension when it's hot. It takes at least 30min of vigorous riding. There are no big penalties for setting it up too loose, except trashing a belt. Too tight is a diaster. I've set my Syncroflex Polyurethane GenIII set hot at about 1" to 1.5".

When Kenny says pull the gearbox backward when you set the slack, he means shove on the case itself. There was so much slack in the one I got from RGM that you need to make sure sleeve them, maybe they are better now. It's a simple piece. I saw some empty gearbox cases at Kenny Dreer's once that had bronze sleeves in the mounting holes. The loads are so far outboard from the fasteners that even if everything is straight to start with, it's going to get cockeyed quickly. You can't tighten bolts enough to keep it from happening if they're a loose fit.

You can get a good idea how square the pulleys are by laying a couple large carpenters squares against them with the perpendicular legs in the middle, comes out at you.

I can't get a straight edge aligned well enough to work for me so the way I make sure belt pulleys aligned properly is first to set cold slack to fairly easy 90's twist, then with front pulley on loose w/o the key and light oilled I spin and spin the primary diddling the gearbox dual adjustors or bumping it tiny amounts if only one adjuster till the belt stays on w/o the front pulley side plates, then mount up fully with plates and key then turn engine over and over and over to make sure belt don't tend to walk off the clutch basket, then final nip up and double check on full heated road use. Check for belt dust evidence its not rubbing too much at front plates or belt edges get frayed and good looking belt can suddenly end up all around the front primary letting ya know ya didn't quick get it right that time. This is speeded up if grit can enter primary somehow.

hobot said:

I can't get a straight edge aligned well enough to work for me so the way I make sure belt pulleys aligned

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arrange 2 carpenters squares like this,

JL

The horizontal arms of the squares are resting on the front of the clutch drum and the front pulley. You would use the long arms for this. The short arms that are pointing at you when you are standing in front of the primary should be parallel if your clutch is square with the pulley. In fact, if you slide the two squares together, the edges of the short arms should meet flush.

hobot said:

....then with front pulley on loose w/o the key and light oilled I spin and spin the primary diddling the gearbox dual adjustors or bumping it tiny amounts if only one adjuster till the belt stays on w/o the front pulley side plates....

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It's always a good idea to check the state of affairs by running the engine with the primary cover off. If the belt doesn't creep in one way or the other the you know everything is OK.

Gosh darn Bob, that two carpenter square method makes me smack forehead on clever sighting tool. Seems some magnets might help out steadyness. Still I'm more a trial and error mechanic than a measure and set kind. Definitely should run the belt w/o front pulley plates on to observe if walking off while kill button at the ready. Belts do flap a good bit when set right, so some light dust expected near the case bosses I found. On a side note I've only ever seen Peel's belt drive with all the anodized blackness coat completely worn out the teeth valley's. Not sure why that was or if its common to others? I had my early learning failures but the andoized coat removal came rather later after everything as should be for long term stability.

This old thread again? Yep. I've been laid up for a few weeks with a back injury, so haven't made much progress on my bike. I'm finally ready to install the dual gearbox adjuster and I'm wondering about orientation. What do you folks think?

Second picture with the adjuster opposing the other. If you do it the other way, with the adjust facing to the back, you cannot use it.

That's kind of what I figured. I just wanted a second opinion before I drill a hole in my engine cradle.

Thanx!

This picture does a great job at showing what you're dealing with when you set the alignment and slack on the belt. You can see how loose the bolt is in the un-threaded adjuster. The same thing is going on with the lower mounting bolt. It's loose in the case and the cradle plates, top and bottom. The final drive chain, (secondary?), pulls the transmission backward with more force than the primary pulls it forward. If you don't push the trans case back against the mounting hardware with your hand before you finalize your adjustment and tightening up then the rear chain is going to do it sooner or later and in the process screw up your slack and alignment.

quote Kenny Cummings a.k.a. Homeslice:
.......as the final drive chain will ALWAYS pull the gearbox backwards, no matter how much you tighten it down.

Understood. Thanks Bob.

If you have the RHS one facing forward can you get to the adjuster nuts after the oil line hardware has been fitted?
Regards Mike

A little progress...

What am I doing wrong? Not quite sure how the stator/rotor and front pulley interface. Would love some help.

Two spacers of differing thicknesses. Should one of these go between gold cap and rotor?


Both spacers are slid together for shits and grins and key is installed.


Outer cap installed. I'm not sure what the two holes in the side of the pulley are for, since I'm covering them with the cap.


Not sure about this piece either. It's on the parts diagram, but there doesn't seem to be room for the rotor to lock onto key with it installed...


Space between cap and rotor. Should these be tight together? Norvil instructions are a little vague.


Stator, cap nut and lock washer.


Rotor and nut installed.


Stator installed. I realize I need to zap strap the wire and that will happen once I get the rest figured out.
Let me know what you folks think. I'm gonna sleep on it....

Did your rotor end up hard against the cap? I'm sure that's how mine is. A bit hard to tell from the photo.
I'd say the two holes in the pulley are for attaching a puller. The original sprocket has them too.
The wire run might be better if you rotated the stator one way or t'other.
Cheers
Martin

It's hard to tell from the picture, but that could be the cupped spacer behind the clutch basket. It's easy to mix it up with the alternator rotor spacer.

060747 Washer, Cupped, Clutch Locating

Snorton74 said:

Not sure about this piece either. It's on the parts diagram, but there doesn't seem to be room for the rotor to lock onto key with it installed...

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rpatton said:

It's hard to tell from the picture, but that could be the cupped spacer behind the clutch basket. It's easy to mix it up with the alternator rotor spacer.

060747 Washer, Cupped, Clutch Locating

Snorton74 said:

Not sure about this piece either. It's on the parts diagram, but there doesn't seem to be room for the rotor to lock onto key with it installed...

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No. That is the Spacer, Alternator Rotor 060402. Apparently not needed with this system.