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Messages - Milt36

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1
Engine & Transmission / Re: Wico magneto wont spark at kick starter speed
« on: May 14, 2022, 08:27:10 PM »
I have always had success with the Megafire electrionic ignition module.  It replaces both points and condensor and has to be installed as if the engine has a positive ground.  About $15 at Amazon.  It may not be stock, but it is sure nicely hidden away.

2
Wheels & Tires / Re: Hub for 1937
« on: March 08, 2022, 12:01:03 PM »
Hi Bob

Hi Bob.  I'm not sure this is the proper place to respond to your email, but here goes.  I live near Montgomery, Texas, about 45 miles northwest of Houston. Sounds like your friend and I have a lot in common.  I have a James ML (restored) and have wanted to get an Excelsior 125 but, as you know, they are very rare.  When I was a kid, my best buddy had one that was chrome plated.  I always thought that was the best looking small bike I ever saw.
I also have a 1947 Simplex which runs but is not restored...was best to keep it simple when my grandkids rode it.  I have a spare Simplex engine as well.

I have enough Villiers 9D parts to build an engine with lots of parts left over including several crank assemblies, cylinder barrels, various gears, clutch parts, etc. A lot of these parts are rough and need re-work.  Villers Services in the UK can rework almost any Villiers part.
I haven't been to Portland but know of it.  My age is beginning to be a factor in traveling so it isn't something I'm likely to do. 

3
Wheels & Tires / Re: Hub for 1937
« on: March 07, 2022, 07:15:27 AM »
I have many parts for the Villiers 9D (some good, some useable with work), if that is the engine you have. 

4
Engine & Transmission / Re: Enlarged exhaust ports
« on: November 17, 2020, 09:00:19 AM »
You're a great craftsman, Pete.  Very nice indeed!!

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Engine & Transmission / Re: Enlarged exhaust ports
« on: November 16, 2020, 10:43:14 AM »
Rick, this particular head is cast iron, but one would think that the larger the port, the more likely the ring snagging possibility.  At least the bridge wasn't removed.  I've only run this engine on the test stand for a few minutes at at time, so I haven't even got it hot yet.

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Engine & Transmission / Re: Enlarged exhaust ports
« on: November 10, 2020, 06:26:12 AM »
Over many years, I've kept up with the progress in 2 stroke performance and know first hand what amazing power they are capable of.  In my last reply, I was making comments specifically about possible performance improvement of the Simplex engine.

7
Engine & Transmission / Re: Enlarged exhaust ports
« on: November 09, 2020, 10:04:28 AM »
Obviously, attempting to gain performance by porting would require a lot of dyno work.  Porting the crankcase at the carb attachment is possible as is changing the timing of the rotary valve, but the intake tract in the head might be the limiting factor.  You could do something at the base, but getting to the ports where they enter the cylinder would be tough.  Also, there would a lot of trial and error involved, with a lot of scrap generated by failed iterations.
Concerning the effect of exhaust port raising on compression, consider this point, if the exhaust port is raised higher and higher, a point is reached where the compression will go down, then in the limit, approach zero when raised to the top of the head. 
So many factors, so little time and money.....probably why it all hasn't been done before.

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Engine & Transmission / Re: Enlarged exhaust ports
« on: November 09, 2020, 07:13:52 AM »
Pete, I agree, someone really skilled put some effort in doing the porting.  Hopefully he got a good result but that is unknown. 
The intake at the carb, the transfer ports in the head are stock are far as I can tell.  A muffler didn't come with the bike. The compression is only 80 psi, but I don't know if the raised exhaust port or worn out bore and rings contribute the low reading.  Wish I had a dyno set up...I could have some fun testing these engines.

9
Engine & Transmission / Re: Enlarged exhaust ports
« on: November 08, 2020, 09:24:21 AM »
Attempted to add photos.....The last one is of an old rusty stock head, the only stock one I had readily available.  The other three are of the ported head.  Was not able to get a scale into the pics, but the comparison to stock tells the story.

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Engine & Transmission / Re: Enlarged exhaust ports
« on: November 08, 2020, 06:56:37 AM »
The ports are in a inclined (to the vertical) oval pattern, will try to get some pictures today....

11
Engine & Transmission / Enlarged exhaust ports
« on: November 07, 2020, 10:00:57 AM »
An engine from a parts bike I bought has a cylinder with enlarged exhaust ports.  I estimate they are about 30 - 40% larger than stock and the porting work seems to have been done very carefully.  The ports are very smooth and symetrical.  After getting the crank redone and replacing the coil, I got the engine running on a test stand set up but can't tell much about the power it may produce.   I know from go-kart work I did many years ago, porting can be easily over done.  Short of putting it on a bike to check it out, does anyone have a feel how the servi-cycle engine should respond to exhaust porting?

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Engine & Transmission / Re: Compression test on H model engine
« on: November 01, 2020, 02:32:02 PM »
For a comparison, I just checked the compression on my James ML 125cc, which has a fresh rebore, new piston and rings, and it registered 125 psi.  It starts with the kick starter with some difficulty if it sits more than a week.  The simplex is a push start model and it sometimes requires starter fluid it it has sat for a while.

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Engine & Transmission / Re: Compression test on H model engine
« on: November 01, 2020, 01:55:56 PM »
Thanks for the reply.  Since I hadn't started the bike in a couple of months, I sprayed a little oil in the cylinder and repeated the test.  This time around, it came up to 95 psi which seems to be a more reasonable value.

14
Engine & Transmission / Compression test on H model engine
« on: November 01, 2020, 11:30:40 AM »
Did a compression test today on my H model engine that was assembled about 10 years ago.  No new parts were used as the bore, piston and rings measured OK.  Result was 85 psi. which I think is pretty good, and power seems OK while riding.  However, I have never seen a number to compare with.  Has anyone checked their compression?  Just curious...

15
What Year is my Bike? / Re: Simplex Model Year Differences
« on: September 19, 2016, 07:56:37 PM »
Mike, after looking over your data base, I've concluded that the direct drive Servi Cycle I had as a kid which I believed was a 1941, must have been a 1939.  The brake pedal was on the left.   It had been upgraded with an H model engine so it ran fairly good.  I posted a picture of it in the gallery.

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