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volksartist
Samba Member
Joined: May 26, 2004
Posts: 264
Location: Muskoka
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 Posted: Wed Apr 09, 2014 12:11 pm Post subject: |
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tobiasax :
Can you share the details of trimming the pistons for non counterweighted crank. I cant find english Okrasa install manual on the net?
Please share details on cylinder shims and push-rod spacing as you guys go!
I have not asked local machinists if they can make me the barrel spacers yet,
prefer not to stack up spacers. I bought pushrod spacers from WW but still
considering a cut to length pushrod option? |
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tobiasax
Samba Member
Joined: May 07, 2004
Posts: 202
Location: Sweden
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| Posted: Wed Apr 09, 2014 1:20 pm Post subject: |
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| volksartist wrote: |
tobiasax :
Can you share the details of trimming the pistons for non counterweighted crank. I cant find english Okrasa install manual on the net?
Please share details on cylinder shims and push-rod spacing as you guys go!
I have not asked local machinists if they can make me the barrel spacers yet,
prefer not to stack up spacers. I bought pushrod spacers from WW but still
considering a cut to length pushrod option? |
Hello, I will keep you posted, but my pace is rather slow, so don't hold your breath while waiting.
The Okrasa instructions is the same as I show, minus the 4 mm cut of the skirt. So, take the drawing in my blog and replace "76" with "80" and there you ahve it!
Last edited by tobiasax on Wed Apr 09, 2014 11:40 pm; edited 1 time in total |
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snowbug
Samba Member
Joined: June 12, 2005
Posts: 167
Location: Oshawa Ontario Canada
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| Posted: Wed Apr 09, 2014 5:28 pm Post subject: |
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| volksartist wrote: |
tobiasax :
Can you share the details of trimming the pistons for non counterweighted crank. I cant find english Okrasa install manual on the net?
Please share details on cylinder shims and push-rod spacing as you guys go!
I have not asked local machinists if they can make me the barrel spacers yet,
prefer not to stack up spacers. I bought pushrod spacers from WW but still
considering a cut to length pushrod option? |
The WW crank comes with .125" spacers to put inside the pushrods. I have made .125" spacers for under the cylinder barrels. Longer stroke will raise compression too. |
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tobiasax
Samba Member
Joined: May 07, 2004
Posts: 202
Location: Sweden
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| Posted: Thu Apr 10, 2014 9:37 am Post subject: |
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Snowbug: What distance did you get from end of the cylinder to the piston top at TDC?
| snowbug wrote: |
The WW crank comes with .125" spacers to put inside the pushrods. I have made .125" spacers for under the cylinder barrels. Longer stroke will raise compression too. |
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volksartist
Samba Member
Joined: May 26, 2004
Posts: 264
Location: Muskoka
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| Posted: Thu Apr 10, 2014 12:32 pm Post subject: |
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tobiasax : OH now I get it! The 80mm portion can be left alone.
Snowbug: I thought the spacers were 2.75mm Can you make me custom
barrel spacers when the time comes? Just getting the balancing
sorted for now...
Last edited by volksartist on Mon May 05, 2014 4:02 pm; edited 1 time in total |
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tobiasax
Samba Member
Joined: May 07, 2004
Posts: 202
Location: Sweden
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| Posted: Sat Apr 12, 2014 3:02 pm Post subject: |
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| volksartist wrote: |
tobiasax : OH now I get it! The 80mm portion can be left alone.
Snowbug: I thought the spacers were 2.75" Can you make me custom
barrel spacers when the time comes? Just getting the balancing
sorted for now... |
Correct Volksartist! (I see that three persons in this thread are from Ontario. Actually my crank has also passed Ontario. Got it shipped to North Bay and took it from there to Sweden.) |
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snowbug
Samba Member
Joined: June 12, 2005
Posts: 167
Location: Oshawa Ontario Canada
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| Posted: Sat Apr 12, 2014 3:10 pm Post subject: |
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| volksartist wrote: |
tobiasax : OH now I get it! The 80mm portion can be left alone.
Snowbug: I thought the spacers were 2.75" Can you make me custom
barrel spacers when the time comes? Just getting the balancing
sorted for now... |
I made my spacers 3mm thick. |
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volksartist
Samba Member
Joined: May 26, 2004
Posts: 264
Location: Muskoka
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| Posted: Sat Apr 12, 2014 5:18 pm Post subject: |
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Vintage speed north!
We have some friends in North Bay with some rare rides....But for a a dude in Sweden that sounds odd!  I have some NOS pistons and dont want to make a mistake! |
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snowbug
Samba Member
Joined: June 12, 2005
Posts: 167
Location: Oshawa Ontario Canada
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| Posted: Sun Apr 20, 2014 5:44 pm Post subject: Re: 36hp Stroker Crank Wolfsburg West |
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| snowbug wrote: |
| Hi , has anyone used the Wolfsburg W 69 mm stroker crank? Any problems? thanks Jim |
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tobiasax
Samba Member
Joined: May 07, 2004
Posts: 202
Location: Sweden
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| Posted: Mon Apr 21, 2014 10:44 am Post subject: |
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This is how my pistons looks like after the mod. Please note that the piston will slide on the wrist pin if not supported by the cylinder so you need to keep it in the middle when trying out any mods.
The 4 mm shorter skirt is to clear the CW and the Okrasa mod is needed for the neighbour crank tap. |
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snowbug
Samba Member
Joined: June 12, 2005
Posts: 167
Location: Oshawa Ontario Canada
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| Posted: Mon Apr 21, 2014 11:05 am Post subject: |
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| tobiasax wrote: |
This is how my pistons looks like after the mod. Please note that the piston will slide on the wrist pin if not supported by the cylinder so you need to keep it in the middle when trying out any mods.
The 4 mm shorter skirt is to clear the CW and the Okrasa mod is needed for the neighbour crank tap. |
I just machined all the pistons last night. They are all NOS. That Hurt a little. Got to the last one and noticed it was different. Its a newer one with steel inserts. I may need to use an old piston that matches weight. |
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tobiasax
Samba Member
Joined: May 07, 2004
Posts: 202
Location: Sweden
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| Posted: Mon Apr 21, 2014 11:41 am Post subject: Re: 36hp Stroker Crank Wolfsburg West |
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| Snowbug: don't forget to take a little material of the rods. You need to do a small chamfer to have a safe distance to the cam lobes, see my rods above. (perhaps you have already thought of this) |
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snowbug
Samba Member
Joined: June 12, 2005
Posts: 167
Location: Oshawa Ontario Canada
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| Posted: Mon Apr 21, 2014 12:09 pm Post subject: Re: 36hp Stroker Crank Wolfsburg West |
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| tobiasax wrote: |
| Snowbug: don't forget to take a little material of the rods. You need to do a small chamfer to have a safe distance to the cam lobes, see my rods above. (perhaps you have already thought of this) |
Yes I did the rod clearancing. So the odd piston is 5 grams different than the others. I dout the engine will go over 4200 RPM. |
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36hplandspeedracer
Samba Member
Joined: January 30, 2006
Posts: 847
Location: Ivins, Utah
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| Posted: Mon Apr 21, 2014 5:13 pm Post subject: Re: 36hp Stroker Crank Wolfsburg West |
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| snowbug wrote: |
| tobiasax wrote: |
| Snowbug: don't forget to take a little material of the rods. You need to do a small chamfer to have a safe distance to the cam lobes, see my rods above. (perhaps you have already thought of this) |
Yes I did the rod clearancing. So the odd piston is 5 grams different than the others. I dout the engine will go over 4200 RPM. |
Snowbug, many of the 36hp Challenge engines are turning up to 6500 RPM's (both singe and dual port) and some even a little higher on the long course's we run. If you are going to "enjoy" your engine, you may want to plan clearancing for higher RPM's just in case.
Burly |
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snowbug
Samba Member
Joined: June 12, 2005
Posts: 167
Location: Oshawa Ontario Canada
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| Posted: Tue Apr 22, 2014 1:09 pm Post subject: Re: 36hp Stroker Crank Wolfsburg West |
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| 36hplandspeedracer wrote: |
| snowbug wrote: |
| tobiasax wrote: |
| Snowbug: don't forget to take a little material of the rods. You need to do a small chamfer to have a safe distance to the cam lobes, see my rods above. (perhaps you have already thought of this) |
Yes I did the rod clearancing. So the odd piston is 5 grams different than the others. I dout the engine will go over 4200 RPM. |
Snowbug, many of the 36hp Challenge engines are turning up to 6500 RPM's (both singe and dual port) and some even a little higher on the long course's we run. If you are going to "enjoy" your engine, you may want to plan clearancing for higher RPM's just in case.
Burly |
Hi Burly I do enjoy my VWs from 25hp to 2 liter with dual webers. The super 36 will have single port with dual carbs. Should have a little more torque to get the Zwitter over the ridge to get to the cruise in. The little Briggs and Straton valves are the restrictor plate of RPMs. Car has a stock 40 pounder in it now and runs real well. The super 36 is not nessary but it is fun to build. All the rotating parts are spinning freely now. The NOS pistons I have seem to be missing 2 compression rings. Any one have some? I have a NOS set and don`t want to break them up. Jim |
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snowbug
Samba Member
Joined: June 12, 2005
Posts: 167
Location: Oshawa Ontario Canada
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| Posted: Sat Apr 26, 2014 11:09 am Post subject: |
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| tobiasax wrote: |
Snowbug: What distance did you get from end of the cylinder to the piston top at TDC?
| snowbug wrote: |
The WW crank comes with .125" spacers to put inside the pushrods. I have made .125" spacers for under the cylinder barrels. Longer stroke will raise compression too. |
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I did a very quick check and I am getting .060 " inch deck height clearance. |
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snowbug
Samba Member
Joined: June 12, 2005
Posts: 167
Location: Oshawa Ontario Canada
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| Posted: Sat Apr 26, 2014 11:11 am Post subject: |
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| volksartist wrote: |
tobiasax :
Can you share the details of trimming the pistons for non counterweighted crank. I cant find english Okrasa install manual on the net?
Please share details on cylinder shims and push-rod spacing as you guys go!
I have not asked local machinists if they can make me the barrel spacers yet,
prefer not to stack up spacers. I bought pushrod spacers from WW but still
considering a cut to length pushrod option? |
here is the piston cleared. |
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snowbug
Samba Member
Joined: June 12, 2005
Posts: 167
Location: Oshawa Ontario Canada
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| Posted: Sat Apr 26, 2014 11:31 am Post subject: |
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| snowbug wrote: |
| tobiasax wrote: |
Snowbug: What distance did you get from end of the cylinder to the piston top at TDC?
| snowbug wrote: |
The WW crank comes with .125" spacers to put inside the pushrods. I have made .125" spacers for under the cylinder barrels. Longer stroke will raise compression too. |
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I did a very quick check and I am getting .060 " inch deck height clearance. |
Another thing I had to do is machine the back of the cam gear. I am using 1600 gears and they don`t line up. Had to take .060" from the flat side. Lines up perfect now and does not rub inside the case. |
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tobiasax
Samba Member
Joined: May 07, 2004
Posts: 202
Location: Sweden
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| Posted: Sun Apr 27, 2014 6:49 am Post subject: |
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| snowbug wrote: |
| volksartist wrote: |
tobiasax :
Can you share the details of trimming the pistons for non counterweighted crank. I cant find english Okrasa install manual on the net?
Please share details on cylinder shims and push-rod spacing as you guys go!
I have not asked local machinists if they can make me the barrel spacers yet,
prefer not to stack up spacers. I bought pushrod spacers from WW but still
considering a cut to length pushrod option? |
here is the piston cleared. |
Looks nice! I did chose to make my pistons symmetrical instead, probably it doesn't really matter. |
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snowbug
Samba Member
Joined: June 12, 2005
Posts: 167
Location: Oshawa Ontario Canada
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| Posted: Mon May 26, 2014 1:25 pm Post subject: pistons |
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| tobiasax wrote: |
| snowbug wrote: |
| volksartist wrote: |
tobiasax :
Can you share the details of trimming the pistons for non counterweighted crank. I cant find english Okrasa install manual on the net?
Please share details on cylinder shims and push-rod spacing as you guys go!
I have not asked local machinists if they can make me the barrel spacers yet,
prefer not to stack up spacers. I bought pushrod spacers from WW but still
considering a cut to length pushrod option? |
here is the piston cleared. |
Looks nice! I did chose to make my pistons symmetrical instead, probably it doesn't really matter. |
Well I seem to be stuck. After checking more closely one of my NOS pistons is 1mm smaller than the rest. Now I have 3 NOS pistons 77.45 and 2 cylinders. Might have to use two old cylinders. Any one need a 76.45 NOS with the skirt cleared for stroker? |
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