Monday, October 26, 2009

S7 Dynamo MC450 (early rather than late MC45L)

Well, thanks to Steve Benson's pix of his dynamo, I took a closer look at mine.  It is likely a forest for the trees type of thing.  The dynamo fitted to my bike only has two brushes instead of four.  I had never seen a picture of one with the cover off.  And I apparently missed this diagram.  (thanks to Phil)


Lucas Model 450 fitted to KYL95.

Apparently there's supposed to be a later Lucas model MC45L.  It must be an improvement.


So the question is ... what to do about it?  Fashion brush holders for the bottom to increase output and balance the load on the armature, or try to get a different dynamo plate or different dynamo / alternator altogether?  Shame I just spent the cash on a solid state regulator, if I would have known that I'd have so much trouble with it, I'd have been more inclined to covert to 12 volts.

First step will be new brushes.  I'll bodge a set if I have to just to see I can get less voltage drop across the brushes and charge better.

Wednesday, October 14, 2009

Autocross United 2008

Val and I had our first attempt at the autocross event at United 2008 in Potomac Maryland. Val's red Imp did very well. In my opinion it bested Eduardo despite his dual SU carbs and electronic ignition, even though our best times were exactly the same, the red car was doing it with a passenger and I was solo. Val was having a ball. It doesn't look fast from the stands... but behind the wheel it feels fast.


I got some wheel lift on some of my runs and was pushing fairly hard.  My harder tires were not helping resulting in sliding around the cones, where Val's softer tires allowed Lil Imp to just sail around the corners as if on rails.

Monday, October 5, 2009

Stable Mates

Its getting a bit crowded in the Imp barn.  I've got two Imps, the bike, a pushmower, and the riding lawnmower all in the basement garage.  The close proximity did cause a bit of a problem during the rebuild of the S7.  I tipped the frame off balance and it nearly hit the red car.  After that I rigged up a rope to the ceiling and kept the bike frame securely tied.  The trick with this arrangement is getting the thing that you want to drive out when its in the back.

 We didn't get many miles on Eduardo this year.  The farthest we went was to Gettysburg for the car show they hold at the outlet shops.  It is an awesome show.  The ladies are content to browse the shops while the guys can admire all the classic cars and bikes.

Thursday, October 1, 2009

First Ride

The S7 Deluxe has been ready, but I needed a license plate to take it out on the street.  The moment I was waiting for arrived today, when the tag and registration came.  I made some quickie retaining clips to hold the plate on over the original UK number plate.  The clips are made of a strip of stainless sheetmetal curved to catch behind the original license plate bracket.  There's a hole drilled in the strip and a bolt welded into that hole so that when the outside retaining nut is tightened the bolt doesn't turn.  The matching brackets attach from the left and right sides and are backed with a strip of inner tube rubber.  This protects the original bracket and gives some elastic tension to the clips.  The clips are made tight enough that they spring out JUST enough to allow the license plate to stretch between the studs.  It is very secure.  Currently the bottom has no clips but simply a piece of weatherstripping behind the plate to protect the original KYL95 plate from abrasion, but I may add some bottom clips later.

You will notice in the film that I forgot to do something as I drove away.  Yup... forgot to turn on the fuel.  I'm so spoiled by the XS650 with automatic vacuum-operated petcocks, and the Guzzi with no petcock.  I got 50 yards down the road and quickly realized what I had forgotten.  I made a few trips UP the hill from my house.  That way if it stops running I can always coast back home.  Unfortunately, its a rather short drive up the hill, so I made a few iterative trips while tweaking the carb.  Overall it runs nicely.  It pulls well even in 3rd gear, and each shift is flawless (unlike the Guzzi).



The best way to see if you've forgotten to tighten any bolts is to see how many fall off on the maiden voyage.  I did pretty good.  I only lost the nut from the distributor breaker contact wire.  It was an easy fix and I was back going again.

There appears to be some oil seepage from the head gasket.  I'll try to torque the head again, but I don't want to snap a stud.  I'm afraid my attempts to seal the oil passageway have failed.  I may be taking the head off again to improve the seal.  I'll have to see what happens when the engine gets good and warm.  Things may seal up as they get hot, or it  may get worse.

My instincts will have to develop for the brake on the left foot.  It will take a while to get used to.  If I can figure a clean an inconspicuous way to add a brake light switch to the front brake I think I will.  Its a safety item and I think its worthwhile.  Learning low speed turning will also be a challenge.  It does get a little squirrely in the turns.  The bike is so well balanced and so low, the counter-steer effect is prevalent even at slow speeds.  I was amazed.  At speeds I tricycle steer with my other bikes, the S7 tends to counter-steer.  That will take some getting used to.

I need to make a little tool-roll of the essential spanners, screwdrivers, and a tommy bar.  Then I will feel better about venturing further from the house.

Electrical upgrades

The charging system just isn't working well enough.  I tried fiddling with the electromechanical regulator with improvement, however if I do get it working its just going to require lots of maintanence, and if it fails then I'm beside the road.  Can't have that.

Rooster Ignitions offers a solid state replacement.  It fits neatly in the original Lucas MCR2 case with the right bolt holes pre-drilled.  A little blue loctite and I bolted it back up.

The ignition system was also upgraded to a booster type solid state device.  Also provided by Rooster Ignitions, the Rooster Booster fits nicely inside the box.  It's strapped tightly to the coil, with multiple Ty Wraps, and doesn't interfere with the ammeter.  I even put a plexiglass cover over the aluminum case just in case the Ty Wraps come loose.  I don't want it to touch the screws on the back of the ammeter.

Now all I need is to install the spare bulbs in the electrical case.  What a neat idea!  I've never seen that before.  This truly is a well engineered motorcycle.