The secret kit under the seat

Forget all those linear voltage regulator designs I posted previously for the Sunbeam Kubota alternator conversion. The error in my thinking is that an unloaded inductor produces high voltages, which must be dealt with by dissipation as heat. My linear design, while still within its design limits, was really overheating cooped up in the box.  It was experiencing too high an input voltage than I planned.  And it was too ugly to mount outside.

So now I know why they use a shunt regulator. It collapses the voltage reducing the power that must be dissipated. Thanks to Electrex World LTD for having model RR-1 in stock, and for the quick shipment.



I made up some clips to go around the seat bolts, and fastened the regulator neatly under the seat out of sight.  With some spare BSW bolts!  It will also get some air flow.

All the original bulbs are back in place, and I'm ready for a test.... as soon as it stops raining.  Initial indications are that the regulator charges strongly.  It doesn't appear to be over the battery rated charge current, and I'm hoping the bulbs will assist in keeping the voltage load regulation in check.

S7 Clutch Release Bearing Mod

The VXB 6x14x5mm Miniature Thrust Bearings arrived today and were easily installed in place of the original balls.  I added some moly grease for extra insurance.  The height gain was only a few thousandths from the worn parts, and easily allowed the clip ring to be replaced with room to spare.

Clutch Release Bearing Worry.

I've been getting an annoying clunk when shifting gears on KYL95.  I adjusted the clutch cold, but when hot it seems not to disengage properly.  Consulting the SOF gurus and Sept/October 2010 issue of On the Beam, I discovered that a modern bearing AKL 6 could be placed between the original release bearing races and maintain the original configuration.  Brilliant, except that I couldn't find that model number locally.

Off to trusty eBay with no results.  So I got the dimensions (6 x 14 x 5mm) and went searching further to discover VXB Bearing selling through Amazon.
http://www.amazon.com/Thrust-Bearing-6x14x5-Miniature-Bearings/dp/B002BBKCAE/ref=sr_1_1?ie=UTF8&qid=1336961575&sr=8-1

They might actually be delivered in two days!

Luckily the clutch release bearing can be removed easily without dismantling the bike.  Pulling it out revealed that there's nothing really wrong with it, except some radial wear inside the bearing holder cup.  Since there really isn't supposed to be any radial load, and I can probably attribute that to some numbskull in the past putting a frapping nail in place of the clutch push rod.

 

The release bearing is easily removed.  Notice my clever Viton o-ring seal "glued" to the outside lip of the gearbox.

 

The locknut is knocked loose, then removed, after that the bolt can be removed. 

 The balls look fine.  There's a little wear on the races, but nowhere near anything catastrophic.  With nothing to keep the balls evenly spaced, I'm sure they're bumping into one another, shifting the load on the races.

 

The whole assembly fits together like this and then drops down into the cup.

 

Sorry for the blurry picture, but the wear inside the cup is evident from some radial load on the bearing.

The next installment will be investigating the installation of the new bearing.

Imp Water Pump

I had a terrible time previously obtaining an Imp Water Pump rebuild Kit through US customs the last time.  This time I was determined to obtain the correct parts locally.

The bearings turned out to be a double-sealed variety which are fairly common.
6202 2RS Double Sealed Bearing 15mm x 35mm x 11mm

The seals were a little harder to find, but a tip from a friend led me to look at pool pump suppliers for an AVON type B seal:
16B36

All is back together and working fine.