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Vintage Whizzer Belt Tension Help

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Henryford2

Finally riding a big boys bike
Need some guidance. This is my first Whizzer build from parts. I’ve read as many posts as I could find on this and other forums on suggested techniques to tension both belts. I thought I was there, but found I couldn’t peddle the bike (too much sheave belt tension?) and after numerous attempts at moving the motor and rear wheel around to get the tension right, I decided to start from scratch.
I’m trying to get to the suggested 3/8” clearance between the pulley and the coil cover. Presently it’s at ¼”. I’ve shown the clutch spring setup and the position of the motor (tight against the seat post) and the resulting clearance. I loosened the motor mount brackets on the motor and swung the bottom of the engine in an attempt to increase the gap, no change (I’ve included a photo of the coil cover with a groove worn it showing that the gap was insufficient in the previous setup). The belt is a PIX A26. The center-to-center distance is 8”. I’m of the impression that swinging of the bottom of the motor does not change this gap, but changes the clutch spring tension. Any suggestions?
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Want to get this right before I move onto the rear belt. As I understand it this is a challenging task on the vintage Whizzer generally requiring much patience and trial and error. Thanks in advance.
 
your engine is too far back ,try moving rear wheel more forward , on the pulley to coil cover clearance 3/16 is adequate when clutch is fully engaged
 
The belt guard is a critical part of the clutch. Placing the guard up as far as it will go without rubbing will provide the most slack when the lever is pulled.

Thought that perhaps the reproduction coil guard insulator was too big in diameter preventing me to move the coil guard up. Took the insulators out and not the case. Unless I hear differently I'm leaving it as is. I have a box full of coil guards and they're all worn in the same place, so I'm assuming I'm not the only one that has had this problem over the last 60 years! Thanks
 
your engine is too far back ,try moving rear wheel more forward , on the pulley to coil cover clearance 3/16 is adequate when clutch is fully engaged

Yes, I believe this is part of the problem. I'm using an AX62 belt on a Monark bike. With the motor back the rear wheel was near the edge of the drop out. The belt was real tight. I'm guessing too tight causing me not to be able to peddle the bike. I've got an AX63 & AX64 belt coming, hopefully I can get the wheel back further in the drop out without being so tight. Thanks
 
Did you get your belt problem resolved? I believe a Monark takes AX63 belt for the rear wheel. When adjusting the belts on a Whizzer , you always set up the rear wheel first.
Set the rear wheel, WITHOUT THE REAR BELT ON THE SHEAVE, TO THE PROPER CHAIN TENSION as you would on a bicycle. Align the wheel in the center of the frame and secure
the bolts. INSTALL THE REAR BELT ON THE SNEAVE . DO NOT MOVE THE REAR WHEEL TO TIGHTEN THE REAR BELT. YOU ADJUST YOUR BELT TENSIONS, FRONT AND REAR BY MOVING THE MOTOR. ALSO MAKE YOU HAVE THE CLUTCH PULLEY AT THE HIGHEST POSITION, WITH PROPER SPRING TENSION.NOTE: the photo of the clutch pulley shows that the AX 26 belt is riding high in the pulley, which shortens the distance between the centerline of the flywheel and clutch pulley. Some pulleys have this problems because the groove was not cut deep enough.
 
Did you get your belt problem resolved? I believe a Monark takes AX63 belt for the rear wheel. When adjusting the belts on a Whizzer , you always set up the rear wheel first.
Set the rear wheel, WITHOUT THE REAR BELT ON THE SHEAVE, TO THE PROPER CHAIN TENSION as you would on a bicycle. Align the wheel in the center of the frame and secure
the bolts. INSTALL THE REAR BELT ON THE SNEAVE . DO NOT MOVE THE REAR WHEEL TO TIGHTEN THE REAR BELT. YOU ADJUST YOUR BELT TENSIONS, FRONT AND REAR BY MOVING THE MOTOR. ALSO MAKE YOU HAVE THE CLUTCH PULLEY AT THE HIGHEST POSITION, WITH PROPER SPRING TENSION.NOTE: the photo of the clutch pulley shows that the AX 26 belt is riding high in the pulley, which shortens the distance between the centerline of the flywheel and clutch pulley. Some pulleys have this problems because the groove was not cut deep enough.
 
Yes and no, I stepped away from this project for awhile (partly from frustration). I had already found out that I needed the AX63 belt, so I changed that, got the correct chain tension and tightened the belts by moving the engine, just as you had suggested. The problem I now have (the belt tension is not excessive) is that I can't pedal the bike, even with the compression release open. With the clutch I can pedal it but it's difficult. I changed the motor pulley when I noticed that the small pulley (rear wheel), was worn badly allowing the belt to sit lower in the pulley increasing the drag (making it hard to pedal?) Made it slightly easier. I have a stamped metal pulley that I'll try next. Without the belts the bike is easy to pedal and the motor with the compression release open can be turned by hand. So I've eliminated the motor and the bicycle as the cause of the drag in pedaling (may be right, may be wrong). Thanks for the help, I've gotten some time today, perhaps I'll get back to it.
 
Yes and no, I stepped away from this project for awhile (partly from frustration). I had already found out that I needed the AX63 belt, so I changed that, got the correct chain tension and tightened the belts by moving the engine, just as you had suggested. The problem I now have (the belt tension is not excessive) is that I can't pedal the bike, even with the compression release open. With the clutch I can pedal it but it's difficult. I changed the motor pulley when I noticed that the small pulley (rear wheel), was worn badly allowing the belt to sit lower in the pulley increasing the drag (making it hard to pedal?) Made it slightly easier. I have a stamped metal pulley that I'll try next. Without the belts the bike is easy to pedal and the motor with the compression release open can be turned by hand. So I've eliminated the motor and the bicycle as the cause of the drag in pedaling (may be right, may be wrong). Thanks for the help, I've gotten some time today, perhaps I'll get back to it.

Technically you should be using a 48 tooth* or smaller chain wheel so as to pedal easier. a 52 is hard to pedal with a Whizzer.
* I would put on as small a front chain wheel as you can stand... if you are far from home, you want it easy to pedal back if it breaks down.
 
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Ok, now what do I look for in the search for a 48 tooth chainring (make, model, manufacturer of bike?) any advantage or disadvantage in going less than 48? Thanks
 
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