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A few pics from two stroke 80 cc engine renovation

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Micke S

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#1
The engine is bult for good power with a stroked high en crank and longer con rod, and the cylinder is ported.

20170429_135549.jpg 20170429_181029.jpg 20170429_185628.jpg 20170430_125436.jpg 20170430_133404.jpg 20170507_112107.jpg 20170507_142720.jpg 20170508_132456.jpg 20170509_194734.jpg 20170509_201428.jpg
 

rzbill

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#2
That looks nice. Porting the transfers for mid range or going for top end with the exhaust port top edge and width? Taking the squish down as low as you can go? Just curious.. Good luck with the project. :)
 

Tozguy

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#3
Zundapp wow, can we see the whole bike when you are done..please please please.
 

Micke S

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#4
That looks nice. Porting the transfers for mid range or going for top end with the exhaust port top edge and width? Taking the squish down as low as you can go? Just curious.. Good luck with the project. :)
This one is ported for strong mid range. The transfer ports are pulled slightly rearwards and the exhaust port is widened on top. Squish band is set to a minimum, 0.55 mm, and cylinder pressure will be on the high side since it doesn't need to rev terrible high. These cylinders provides max power @ 9800 rpm stock. The combination with 3 mm longer stroke and tuned exhaust will give a meaty mid range for good driveability. It will also have a fixed electronic ignition system, which I modify myself for an automatic retarding curve, starting at about 30 degrees BTDC on idle and falling to about 15 degrees on full rev. This is a solution that is used on many small classic bikes here now.
rp2-krom.JPG
 

Micke S

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#5
Zundapp wow, can we see the whole bike when you are done..please please please.
This engine is not for an own vehicle but here is a picture of one of mine Zundapp's.

DSC06425.JPG
 

Tozguy

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#6
Thanks Micke, what a thrill to see an old classic in such terrific condition.
Mike
 

rzbill

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#7
This one is ported for strong mid range. The transfer ports are pulled slightly rearwards and the exhaust port is widened on top. Squish band is set to a minimum, 0.55 mm, and cylinder pressure will be on the high side since it doesn't need to rev terrible high. These cylinders provides max power @ 9800 rpm stock. The combination with 3 mm longer stroke and tuned exhaust will give a meaty mid range for good driveability. It will also have a fixed electronic ignition system, which I modify myself for an automatic retarding curve, starting at about 30 degrees BTDC on idle and falling to about 15 degrees on full rev. This is a solution that is used on many small classic bikes here now.
View attachment 233243
Perfect goals for a fun and sprightly ride. I'm not a fan of pushing everything to the top end. Good luck!
 

FOMOGO

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#9
Looks like you had to do a little clearancing for the stroker setup. Those little two strokes can make some real power with a little massaging, and it looks like you have it down. I had one of the first 360 RT Yamaha's when I was over-sea's in the early 70's, it ran like crap when I got it. Took it to a bike shop in Okinawa and after about 15 min. of cutting and welding on the exhaust and a little carb tuning, the thing became a total animal. Cheers, Mike
 

Micke S

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#10
4a938bcecb2909ec079e5255b10ca8c9.jpg

I have been in the US many times both on work and holidays, and was not planning to do it again. But...I've got a call from a friend i Sweden today who asked if I would like to make a road trip on Route 66 by motorcyle from Chicago to Los Angeles.
Do bears be ****tin' In the woods and when will we go was the answer.
 

Tozguy

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#11
Micke, have you ridden the Blue Ridge Parkway in Virginia and North Carolina?
 

Micke S

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#13
Micke, have you ridden the Blue Ridge Parkway in Virginia and North Carolina?
Hi, no but I would love to go there !
 
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