Author Topic: Building Val a one cubic inch four stroke single  (Read 89381 times)

Offline Art K

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Re: Building Val a one cubic inch four stroke single
« Reply #360 on: July 05, 2017, 03:24:28 AM »
Dave,
Thanks, I will have to do some fine tuning but I am happy with the first run.
Art
"The beautiful thing about learning is that no one can take it away from you" B.B. King

Offline Roger B

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Re: Building Val a one cubic inch four stroke single
« Reply #361 on: July 05, 2017, 08:15:13 AM »
Excellent  :praise2: I would be more than happy with that as a first (second  ;) ) run  :ThumbsUp:  :ThumbsUp:  :wine1:
Best regards

Roger

Offline b.lindsey

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Re: Building Val a one cubic inch four stroke single
« Reply #362 on: July 05, 2017, 12:36:25 PM »
Well done Art!!  Its always a nice feeling seeing and hearing them run that first time, and most just seem to run better with some age and running in too.  :ThumbsUp:

Bill

Offline fumopuc

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Re: Building Val a one cubic inch four stroke single
« Reply #363 on: July 05, 2017, 07:15:21 PM »
Hi Art, good to see another runner. Congratulations.
Kind Regards
Achim

Offline Art K

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Re: Building Val a one cubic inch four stroke single
« Reply #364 on: July 08, 2017, 11:46:40 PM »
Achim, Bill & Roger,
Thanks, I now have a short progress report. I brought it out with me to Akron, PA for the family reunion. It fired up right away. I did have a minor problem on the last run. One of the screws holding the rocker arm in place fell out. Nothing catastrophic, just shut off the ignition. It fell on top of the cylinder head bolt, picked it out with a screw driver. I think I'll put it in with loctite. Ran it about 5 or 6 times for a total of 15 or 20 minutes. It isn't balanced as well as the Upshur so I've not been able to really fine tune the high speed mixture due to not having three arms.  :ROFL: When I get home I think I'll clamp it to the picknick table and give that a try. It will run about 5000 rpm in present tune, just a guess. I have noticed that it runs considerably hotter than the Upshur. I said It was pretty hot and my wife's uncle naturally had to touch it to see. :lolb:
Art
"The beautiful thing about learning is that no one can take it away from you" B.B. King

Offline Art K

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Re: Building Val a one cubic inch four stroke single
« Reply #365 on: July 11, 2017, 04:17:15 AM »
Hi all,
In my limited time in Pennsylvania I stopped in to see Phil and his friends at the 717 maker space. And thus ran full speed into problems with Val. Wouldn't start up right off the bat due to no compression. Sorted that out, valve adjustment. It then ran great, till the push rod came falling out and the roller for the rocker arm fell out. I did find all the parts but came to realize that there is a problem. Seems the pounding on the roller elongated the reamed hole the pin is pressed into making it a slop fit. Did I choose the wrong grade aluminum. Does anyone have anyone have any ideas. Do I redo the part in steel? Change the sizes and try again? Is there a needle bearing that would work with a modified rocker? any help or suggestions would be helpful.
Art
"The beautiful thing about learning is that no one can take it away from you" B.B. King

Offline Brendon M

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Re: Building Val a one cubic inch four stroke single
« Reply #366 on: July 11, 2017, 08:56:32 AM »
Hello Art, congratulations on getting Val running!

As for your problem, I can only offer some limited advice.

It's a question of reducing the yield stress (by making the part larger) or increasing the yield strength (by using a stronger metal)

Given that making the part larger will possibly mean having to change the dimensions of other parts, you might be better off using a stronger metal. I hope this helps.
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Offline Art K

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Re: Building Val a one cubic inch four stroke single
« Reply #367 on: December 03, 2017, 12:12:19 AM »
Hi everyone,
I thought that I would add to this rather than start a new topic. After some thought I've decided to make a new muffler. It seems that it should wind out a bit higher RPM. So the muffler being the easiest to change the old one is getting the axe. I've modified the exhaust flange and made the portion around the mounting holes bigger, beefier. Does anyone have any thoughts on muffler design? I'm planning to use brass tubing 7/16" OD for in/out and 3/4"OD for the muffler center section and silver solder it all together.
Art
"The beautiful thing about learning is that no one can take it away from you" B.B. King

Offline Art K

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Re: Building Val a one cubic inch four stroke single
« Reply #368 on: December 18, 2017, 02:04:42 AM »
Hi everyone,
I had a go at making a new muffler for Val. It was a 7 piece affair with a bunch of 3/16 holes in the 7/16 tubing, a cap over the end of the inside tube. With the exhaust flange (the first part I've made with pathpilot) and the end caps turned to fit the 3/4" tubing, and soldered in place. I ran it the other day trying to tune the high speed as fast as it would go. It kept stalling I think I might have run it a bit warm. It being in the 40's today I thought I'd run it a bit today. I kept hearing this unusual tinkling noise. Then it would act weird and just barely run. Turns out I blew the soldered cap out of the end of the inside of the muffler. Then it was pushing itself against the outlet. I've unsoldered the end and now have to rethink the way I made it.
Art
"The beautiful thing about learning is that no one can take it away from you" B.B. King

 

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