A rider ...

[Ricks]

Pete, you better have that bike running so you can ride with us!  I think I will have the stretch up and running, all in bare steel!  If we have rain like last year, I will not have to paint it, I can run with the patina.

[pd]

Ha . Patina ... My '57 has gained a bit of patina sitting on the trailer for the last 8 months . It sure doesn't seem that long .

I had problems crop up with both my XT350 and the FA50 recently . Those are both back in shape , so now I have the '57 to contend with . I swear , I've never had a motor give me so much grief as this little Simplex .

Pete .

[pd]

Today , I started work on my bike .

Checked spark : redish purple . That's real pretty , but , I'd rather see a fat white spark . I'm wondering if that red spark is being blown out before it does any good . I know that can happen in some of the Honda in line 4s .
Checked compression :  105 pounds . I'd rather have half again as much , but , I've read that these motors can run on as little as 60 pounds ( I find that amazing , if true ) .
What is the normal compression of these motors ? Maybe I missed that in the manuals .

Tomorrow , I'll pull the carb and give that a thorough cleaning and check float level .

Pete .

[Ricks]

I have tested compression on 3 motors that I have built, and all have been between 75-90 psi.  Wayne has told me in the past they will run at 65 psi.

[pd]

That's likely what I'd read . Your mention of the 65# .

At 100+ pounds , I should be fine . I just have to get the thing to run .

Pete .

[pd]

Progress report :

I pulled the flywheel and found a bit of moisture . Removed that with a spritz of brake cleaner ( works great ; easy on rubber / plastics and leaves no residue ) . I also found a fairly loose high tension wire connection to the coil . Tightened that and replaced the flywheel . Then tested for plug spark : crisp white sparks .

I tried to start the motor , but noticed that the fuel line was mostly filled with air . Allowed the air to exit by loosening the upper fuel line fitting .

Tried to start it again . Choke , no go . Choke with my palm closing off the air filter and after a few rounds the motor came alive , but wouldn't stay running . Messed with  the carb adjustment screws and got to stay alive at a high idle . All that with no load ( released the transmission tension spring ) .

By this time the motor was getting very warm . I plugged the house fan in and aimed it directly at the cylinder . Hit the high speed button .

Then I reset the transmission spring and had to adjust the carb  a bit to keep the motor running , under load .

It was time for dinner ... got back to a cooled motor and tried to kick start : not a chance . Resort to power start with success . Released the transmission spring again and tried a kick start and it started nicely and gains RPMs with ease .

That's where I left it for the night .

Pete .

[Ricks]

Pete, solder the high tension wire to the coil.  I have found with the Carpenter reproduction carburetor that the screws need to be opened at least another half turn than the stock Tillotson.  I start at 1 1/2 turns out on each, and sometimes end up around 2 turns out.  Be careful not over tighten them.  I have used 3 of these repro carbs now with great results.

[pd]

Rick ,

I ran the motor a bit yesterday and noticed that it wanted to lope a little and then finally die . I'm wondering if the fuel metering tube could cause that .
How many tube side holes do you run ? IIRC , you drill extra to match OEM .
I tried that with the MT9 carb but closed one set of holes with better results . That may have been because of different size tube end holes . A while back , I asked a question about the end hole size , but never got and answer from anyone .

http://www.simplexservi-cycle.com/index.php?topic=1341.msg11796#msg11796

Pete .

[Ricks]

I have spoken to Wayne about drilling the extra holes.  He says he has done both and has not noticed much difference.  I have to agree with him, as I drilled them on my 2 simplex automatics, but not on the Sportsman, and I see no difference either.

[pd]

OK , then I have to look for a different reason .

Maybe I have too much 'stuff' packed in my exhaust 'can' . I could try pulling everything out , but that'll make it pretty loud .
I'm grasping at straws .

Pete .

[Ricks]

OK , then I have to look for a different reason .

Maybe I have too much 'stuff' packed in my exhaust 'can' . I could try pulling everything out , but that'll make it pretty loud .
I'm grasping at straws .

Pete .

I don't think you should have anything packed in the your can!  lol 

[pd]

OK , then I have to look for a different reason .

Maybe I have too much 'stuff' packed in my exhaust 'can' . I could try pulling everything out , but that'll make it pretty loud .
I'm grasping at straws .

Pete .

I don't think you should have anything packed in [the] your can!  lol 

When you put it that way , I definitely agree .

[pd]

Today , I pulled a little bit of fiberglass out of my muffler can . There wasn't near as much as I had put in there . I think the burnt fiberglass fairy took some for her collection .

Then I started the motor to see if there was any noticeable difference . It ran just long enough for me to make out two decibels difference before it ran out of gas . I couldn't find my premix oil , so it's a good thing there's usually tomorrow .

Pete .

[pd]

I made a rookie mistake .

I took compression readings while using power to rotate the crank ( much higher RPMs ) , instead of using the kick lever .

So , instead of 100+ pounds of compression , I'm lucky to get 60 , with a very brief threat ( needle bounce ) close to 65 pounds .

No wonder the thing won't idle down , let alone start with the kick lever .

 I'm basically at the same point I was 3 years ago when I rolled the bike out of the barn . Worse really . At least then I could kick start and ride for a few minutes .

Pete .

[Ricks]

Did you put rings in the motor? If so, what is the gap?