whats up with the punsun v twins?

Engine's, injection, valve's, timing, crank's etc..

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thundercougarfalconbird
I luv the smell of Diesel...
Posts: 120
Joined: Sun Jun 15, 2008 4:52 pm
Location: sexsmith , alberta , canada

whats up with the punsun v twins?

Post by thundercougarfalconbird »

hi everyone, its been a long time since my last post, after getting my diesel bike running and only getting about 600km of riding time on it, not terribly happy with the way it was running (140km/h) topspeed, and too much smoke i have decided to add a turbo.

Removing the engine and dissassembling the engine has revealed some interesting things...
1 the crank shaft is not welded on the crank pin but the weights are welded in place.
2 there is a oil by-pass valve , but also a drilled passage that sprays across the case, not sure what the deal is with that.
3 after spending som time with a dial indicator and degree wheel, the v is not 90 degrees, its 80 degrees, one more reason the odd exhaust note.
Having the degree wheel in place makes it so much easier to dial in the goofy injection pump, a few modifications and possibly a few parts from china and i will be turbo charged, everything seems to be running well, no damaged parts so far.
After emailing Frank at mgs in china he has told me they have changed about 80% of the parts on the new 22 hp engines, i guess they are making progress with this unit.
oh the fun and games :D

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I'll do what i feel.
albertaphil
I luv the smell of Diesel...
Posts: 212
Joined: Sat Aug 01, 2009 2:23 pm
Location: northwest of Calgary, Alberta, Canada

Re: whats up with the punsun v twins?

Post by albertaphil »

Hey TCFB (by the way, I like the Simpsons reference:-),

So it's never quite enough, is it? Good job with Punsun investigation. I'll let you get everything figured out, and then I'll get one:-) I'm slowly getting along with my 16hp Ruggerini twin powered Honda (subframe in place, transmission figured out, working out the primary drive with Martin Sprockets.) I'm hoping that it will be good for an honest 65mph up some not-too-steep hills, but I'm not holding my breath. In the event that it is not quite what I hope, I'm planning to turbo it. What turbo did you get, or are you getting? There was quite a bit of talk on this forum about restricting oil flow to the turbo, which seems like a really bad idea to me. What have you done in that regard?

Anywho, Sexmith must be the hotbed of dieselbikes in Alberta, what with you and BoxerOtto. I'm pretty lonely here, so if you're ever heading down this way, feel free to stop in and show me your ride.

Phil
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thundercougarfalconbird
I luv the smell of Diesel...
Posts: 120
Joined: Sun Jun 15, 2008 4:52 pm
Location: sexsmith , alberta , canada

Re: whats up with the punsun v twins?

Post by thundercougarfalconbird »

its actually a futurama reference, but not big deal, and enuff is never enuff for power and speed, as for sexsmith being the hotspot, well not sure about that, boxerotto is my brother, he has pix of his build on the site as well.
I cant remember the brand of turbo, but its the little turbo used on rhinos and such units, restricted oil flow is a silly thing to do to a turbo, the plain bearing in the turbo will govern the proper oil flow and only what leakes past the bearing flows back to the crank case, the drain needs to be free and open to the case, i will get all that sorted, just spending alot of time with timing at the moment.
best of luck with your build phil , maybe one day will will pass on th highway, or meet at a fuel station
I'll do what i feel.
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