HolmenTree bikesaw projects.

[ehp]

Oregon harvester chain the new stuff is far better than the chain you have as far as cutting speed goes, the tooth is taller , yes its .063 gauge but your chain is .058 gauge up at the top so only .005 bigger plus the .063 is far stronger

[HolmenTree]

in 22 inch wood without high tooth I donot care how much power you have you will not be even close , one thing you need to think about is your port timing , motor is shut off and you start it on go , if your porting is to high the motor will not spool up in time so the race is already over before you even touch the wood , . Having lots of power for the 3rd cut is way to late

All good advice Ed, but even though my YZ125 has the exhaust at 202° it's still a hyper quick 50mm stroke 125cc engine. It's VForce 3 reed cage and TRX style custom drag pipe will have her at WOT into the first cut.
My CR250R port timing will be at 190°/129° also with a VF3 reed cage and drag pipe.

[HolmenTree]

Oregon harvester chain the new stuff is far better than the chain you have as far as cutting speed goes, the tooth is taller , yes its .063 gauge but your chain is .058 gauge up at the top so only .005 bigger plus the .063 is far stronger

Are you sure that harvester chain isn't. 080 gauge?
I don't think there's enough sideplate on a semi chisel harvester chain to make it into a proper square chisel.
Matter of fact I see some shows are banning harvester chain because of it's high chain shot forces going through safety shields.
The 46RST HT is not such a big deal, guys like Mel Lentz complain it stretches bad, weak and depth gauges too low. 
I'm not shy to put 40 hours into my 50AL race chain. With the matched sprocket gearing for the competition's diameter of log, I'll have it under control. 

[ehp]

there is different depth gauges setting on high tooth, All your fast times are cut using high tooth or 1/2 inch . the chain fills under the cutter and once the tooth is full it cuts no more wood , Believe me we tested a lot and high tooth on 3 cuts in 20 inch is over a second faster and closer to 2 seconds. I have some taller tooth .063 Oregon here we tried from harvester . Its ok up to about 12 inch wood , anything bigger the higher tooth takes over . You geared down pretty good to , A stock 250 will scream a 16 tooth gear using high tooth chain . High tooth is stock stihl chain with just a taller tooth , some guys pull the tooth off and use .080 gauge setup and the harvest chain is chisel not semi , It pays to know people lol, I spent lots of time in Oregon plant here on making my own high tooth chain . Only problem was the plant was booked for at least 2 but more likely 3 years making chain

[ehp]

well then you should know , the bigger the diameter of log the higher number of tooth the gear needs to be so the cutter cuts the full way across the block . If your cutter gets full it stakes the rest of the way across the block and starts bouncing in the cut . The chain your using we played lots with and went as high as 24 tooth gear on a rotax and after 20 tooth it made zero difference as was still a lot slower than high tooth setup running a 16 or 17 tooth setup

[HolmenTree]

Ed, yeah I missed out on the Stihl HT chain. Could have easily bought some loops a few years ago from J.S.B. Called him last fall and he said their gone.
Jerry Gingras set a record with the 46RST. 404 years back beating his 1/2 inch times.
The chain has been around for almost 20 years now. Hopefully the rumor it'll be replaced with a newer version...as long as there still is a Stihl Timbersports.

I was in the Guelph plant on a tour back in the early 1980's. Lots of history in that place.
It used to be Planer Chain Ltd Guelph, Ontario Canada.
Oregon bought Planer out in 1952.
1957 the company changed its name to Omark Industries but still keeping the Oregon brand name.

Here's some pics of the Stihl 46RST high tooth.


 

 

[snowstorm]

Most harvester chain is 404.  80 Stihl make 2 versions. 1 is stronger. Oregon 18 or 19 x

[HolmenTree]

Most harvester chain is 404.  80 Stihl make 2 versions. 1 is stronger. Oregon 18 or 19 x

The last .063 harvester chain I ran on my Stihl 090-60" was the older Stihl chain . I thought everything went .080 every since.
I got a 12T .404  NOS Sandvik .063 harvester sprocket to run on my YZ125 and ordered a 14 also. The hub adapter is getting made at the moment. 


 

 

[HolmenTree]

To swing those bikesaws this equipment is very important.
I'm 62 and still using them everyday for over 40 years now
This is my gym in my laundry room. 

[HolmenTree]

Winter of 1989 running my YZ125.

Brother's Mac 101 kart saw beat me that day.
The experimental pipe's long stinger didn't work out.

[HolmenTree]

Brother Dennis with his 101 Mac with 34mm carb, inverted pipe stinger.

[HolmenTree]

Also on that day Peter Holmquist Husqvarna distributor from Vancouver (originally farmed near our Saskatchewan farm) is running the first ever Husqvarna 3120XP in North America with a pipe. ;D


 

[Walnut Beast]

Yes sir!! That's right! Getting after those weights makes a difference🏋️‍♀️🏋️‍♀️💪💪

[ehp]

Jerry set a lot of records but if your talking about the 20 inch Boonville record I think was in 2017 , maybe a different year than that but I seem to know that chain very well he ran ;D, Dave won 2018 Boonville with a stock bore stock stroke  cr 250 from here . Just like everything else as time goes on things get faster

[HolmenTree]

Jerry set a lot of records but if your talking about the 20 inch Boonville record I think was in 2017 , maybe a different year than that but I seem to know that chain very well he ran ;D, Dave won 2018 Boonville with a stock bore stock stroke  cr 250 from here . Just like everything else as time goes on things get faster

Yes it was the 20" Boonville record. There was discussion about it a few months ago on another forum talking about the high tooth chain.

Yeah those short stroke CR250 honda are pretty impressive. With my CR250 build I'm going into a whole new uncharted territory.
My '83 has the same basic bore/stroke and porting as the newer ones with non PV TRX design cylinder and CR500 style head.
A guy posted  his bikes dyno  sheet for his 1986 68mm x 72mm short rod  CR250 making 261cc.
Max power 57.05 at 7,460 rpm
Max torque  40.49 at 7,300
at the rear wheel!

It's going to be later this summer when I get the Honda in the wood, got to get the Yamaha done first so I know what to do with the Honda.
I definitely will find some .404 high tooth chain, I may have to pay a king's ransom for it though.
And definitely will run a 16T gear on it.
I thankyou for your usual good advice Ed. Hopefully I can get my tree service season started up this year to help pay for these extra custom parts.
Are you doing any logging?
They do need toilet paper and masks!!

[ehp]

logging 7 days a week, just got home. What rpm are you spinning motor at . I know the cr 125 Honda I built the pipe for sure cut really well , Pipe was built for 11,250 rpms . Motor was stroked . It ran 3/8's chain but was never suppose to be in big wood . Big wood I would be running high tooth

[HolmenTree]

logging 7 days a week, just got home. What rpm are you spinning motor at . I know the cr 125 Honda I built the pipe for sure cut really well , Pipe was built for 11,250 rpms . Motor was stroked . It ran 3/8's chain but was never suppose to be in big wood . Big wood I would be running high tooth

Good to hear you're busy putting timber in the landing!
The honda cr250r I haven't got it together to run yet. Got all new parts plus spares along with spare cylinder and crank. Enough to build 2 motors. One cylinder 66.75mm the other 68mm , both never ported, bores are mint and ready for a fresh hone.
It will run the 28" roller bar , 16T & 46RST, cone pipe, PVL analog ignition and SBN 38 carb.

The YZ125 I never had a tach on it, but with the factory 202°/129° port #'s it's peaky.
New cone pipe will be built and see how it runs with the SBN 38. Already setup and run in with the new PVL analog ignition.
It'll just run primarily the short roller bar and got it setup for .404 now .
Should have it in the wood in a few weeks.

[HolmenTree]

So I'll try  both saws with the Mikuni SBN 38mm jetski gas carb. Then if it works out for both, the next new SBN 38 I'll buy will "probably" be a alky carb.
Not sure yet which motor will get the alky carb and the other running race gas.


 

 

 

[HolmenTree]

3.5 oz bar oil tank inside a 17 oz fuel tank. Got it all figured out now, just need to install 4 aluminum 1/4" fittings on the back, get it all tig welded together then cut the top to accept the gas/oil cap top plate and three bond 1194 gasket.



 

[HolmenTree]

Almost ready for tig welding.


 

 

 

 

[Evanguy]

Holemen tree, wow i see this is not your first rodeo, its deffently mine so im excited to read this thread and learn. You have been doing this since before i was born ('85)

Also yeah the '83 top end wont fit on the 84 bottom end, if it did i would have used the 83 head to save weight and time. But ill just cut off the atac box on the 84 head to clean it up and make it lighter

I just ordered new rings and crank bearings for my build.

Im  a manual machinist who mainly runs a mill, but ive been layed off due to this covid 19 so my progress is slow right now.

What do you think about using the coolant jackets to hold the bar oil, and the drain hole as the output then pressurizing it with a small tube from near the stinger of the expansion chamber

Thats an awesome carb, now that i look around a bit more i notice lots of hot saws runs those carbs, they are off a jetski? What is the advantage over a flatside dirt bike carb? Say like a keihin pj 38 or a pwk 38 airstriker.

Once some more of my parts get here ill start a thread on my build. Also i hope to get into work for a day to get some work done on it. And back and forth if i should cut the cases. It will save a little weight but i have a hard time cutting stuff that is hard to come by ( i restore lee metfords and lee enfields as my main hobby)

Awesome thread, its been real helpfull.

There no chainsaw compaitions around here..so im building this just for fun so i can cut cookies in my yard. Can i use a 404  .080" harvester bar and chain with a 16 tooth rear? Or will the chain come off with out a fatbelly bar

[HolmenTree]

There are many good competitions in the Maritimes many competitors into the Stihl Timbersport teams.
You gotta start somewhere in the smaller shows.

Your engine will be in a standup vertical profile so yeah bar oil in the cylinder water jacket works well. You really don't even need to pressurize it.
Just an inline valve to turn it on and off and let gravity and the suction of the drive links do its job.
My horizontal profile saw I need to keep all the extra weight I can at the front of the saw for good balance.

Yes that's a pumper jetski carb. I ran chainsaws most of my life with 2 adjustment screws and that's why I like this carbs setup.
I know nothing about dirt bike carbs.

Yes a .080 harvester bar is a good idea starting out, of course you'll need a .080 chain to match which unfortunately is semi chisel.
But with a motor pushing 50 hp semi chisel doesn't really matter for someone learning the ropes.
Just make sure no one is standing at any distance in front of your saw while your cutting . Think of shooting your 303 Lee Enfield rifle.

If that chain breaks "chain shot" can pass through a solid steel guard.
Know your limitations!!

Matching the tail to a 16T .404 sprocket is so important that's where a harvester bar to match that diameter is so important.

One of my favorite rifles I owned is a Lee Enfield MK IV .303
I had a 4X scope on it and the rifling of the barrel was very good straight shooting. Tough rifle.
I heard  some of our WWll vets tell stories that they could smash a door open with the butt of that rifle.

[Evanguy]

Thank you, and nova scotia is a nice place. i like it here, i from the halifax area but moved out of the HRM a few years ago now.
  
Ill have to check out some of the smaller shows and see whats up. I think there are some around but i cant really find any info online. Also im more so intrested in chainsaws then axes. Although that may change

Also this has been very helpfull to me. Loads of great info.

I got my top handle waterjetted out at work, still need to find time to weld it up between all my other projects lol.  I also sold all the inners of my 84 bottom end. So ill be cutting the cases to remove the transmission section.

Did you get any more work done on your motors?

Im going to start my build thread once this handle is finished. 

 

[ehp]

remember vibration is your real enemy so make sure you have as close to zero as you can get . the more the saw vibrates the harder it is to keep the chain on it . If your using .080 gauge chain you can buy bars from Oregon that fit up to 18 tooth , the one harvester  runs a 17 or 18 tooth gear

[snowstorm]

i run a ctl harvester. i like sthil  chain doesn't break as often as others. sthil makes 2 one is heavier. oregon 18x cuts as good but weights less if that matters to you. the new 19x i was told takes a lot of hp. i have not tried it. a oregon speed max xl bar comes in lots of different widths and taper towards the sprocket. all 404  80 rakers at .050