HolmenTree bikesaw projects.

[HolmenTree]

CR 500 chainsaw - YouTube

[mike_belben]

Yeah exactly.. They have so much piston pushing on so much crank that they dont need rpm. Probably dont have the carb and ports for putting it all up top id bet.  But they can torque out of any hole in any gear. 

I had a husky 250 when i was about 13 .. I think it was a WR.. Similar power but you could use it a lot more often than a 500 in the woods.  It was flat power from bottom to mid.. Once you used up the mid it would rev higher but not pull harder.  If you upshifted it dropped rpm back into the curve and pulled again.  Whenever the rpm got low it had almost excess power, [for a kid anyway] almost didnt matter what gear. 


When i got a 450R fourstroke quad.. That was similar.  They feel like big blocks.  Like a truck engine in a minibike.  A cat 550 isnt that much different.  Keep piling on weight and they just keep pulling it up the hill without revving any higher.  Torque is nice for lazy riding. Its tolerant or your errors and doesnt take 3 shifts to fix a bog at the bottom of a hill. It just ripsaws its way up. Braaahpp.  

I probably cant even start a dirtbike anymore.  Now im feelin old!

[HolmenTree]

The CR500 will sing at top end at about 7500 rpm by raising the exhaust port enough and milling .080" off the head.
Lots of potential. 

[HolmenTree]

I'm slowly piecing the 1984 Honda CR500R 514cc hotsaw project.
The new OEM short rod crank came tonight. Now I can do a mock up profile picture.
It will look much different when near finish,  2/3rds of the cooling fins gone, no transmission housing.
Major porting will be done with other bolt on performance parts greatly exceeding its stock 60 hp and 50 ft lbs of torque.

[HolmenTree]

I'm trying to decide what size .404 sprocket to put on the CR500
The 500 has the same size pto crank spline as the 250.
The 500 will peak at around 7000rpm with about 50 foot lbs of torque so I'm thinking no less then 16T .500"

[HolmenTree]

So here is the Honda CR500R crankshaft.



 

[Tacotodd]

Whhaaaat?????? I thought that you always went OE on pieces on “most” saws. I guess that this doesn’t qualify though ;D

[HolmenTree]

In my last post I forgot to mention the evolution design of the Honda CR series crankshaft.

In the first pic below here's some more pics of my NOS 1983 CR250R crank for again comparison to the crankshaft for my 1984 CR500R engine.

1984 was the first year Honda went to the "tin can" web covers, the 1983 was the last year for solid webs and internal stuffer plates this design went on into the 1990's formula 1 road racing bikes.
1984 was also the first year for Honda's Pro lite design piston in the CR250 and CR500.

So my 1983 250 has a good foundation for a highly modified top end cylinder.

Last 2 pics are the mighty  91mm CR500R piston.  
To show the versatility thinking of Honda this piston will fit a 1982 CR480R all the way to 2001 CR500R.



 


 

 

[HolmenTree]

Whhaaaat?????? I thought that you always went OE on pieces on "most" saws. I guess that this doesn't qualify though ;D

Hehe, yeah I had to do a little editing to keep in good standing ;D

:D

[Tacotodd]

10-4! I was wondering.

[HolmenTree]

Well tonight my YZ125 and CR250R bikesaw carbs came in.

[Tacotodd]

Beautiful!!!  I was also wondering about your cataracts. Any update? Or am I mistaken? After all, any thing is possible, and some things are are highly probable. 

BTW, good to see you out there still plugging away!

[HolmenTree]

Beautiful!!!  I was also wondering about your cataracts. Any update? Or am I mistaken? After all, any thing is possible, and some things are are highly probable.

BTW, good to see you out there still plugging away!

Hey thanks. 
Yep just finished my last eye last week. Got 2 new "made in Texas" lens installed, and all I can say is WOW with the bright colors I look at and no more cloudy white glare . Like cleaning a very dirty window.  :D
Due to the time frame of my double eye surgeries I have to avoid dust and heavy lifting, I've been taking it easy doing R&D.

[Tacotodd]

Isn't it hard to do much R&D? I mean, no heavy lifting and all. 

Don't get me wrong, I know that quite a bit of R&D can be done just doing the "paperwork" research, but real world development comes from your doing it. And YOU are a hands-on type of man! I know that you are just ITCHING for that time (however long it is) to have passed. But even then, take it easy and follow the Docs orders. 

Just don't be TO sedentary, blood clots might develop. Best thing that I've seen, hand wash some dishes. 2 things happen from that. It gives great appreciation for dishwashers, and makes you understand some of the lifestyle of a much older generation (back in the day)!

[HolmenTree]

Tacotodd, well said. I can relate to alot of what you said.
When I was a kid on the farm running water was me running to the well with a bucket. 

[HolmenTree]

Update on the 3 bikesaw projects,
Covid seems to have for certain cancelled any hope for 2021 competitions, so taking my time with these  saws.

This morning bought this 4.5" wet tile saw on sale for $48 USD to add to my carbon fiber arsenal of cutting tools.
Also a pic of the latest sheet of 5mm CF for the CR500R saw.
The Honda 500 will also get the same Jonsereds 601 rear handle design as the 125 and 250 .


 

[Tacotodd]

Glad to see you back at it. We were ALL wondering about you, and are glad that you are back to contributing to our, ahem, excuse me, addiction.

[HolmenTree]

Glad to see you back at it. We were ALL wondering about you, and are glad that you are back to contributing to our, ahem, excuse me, addiction.

Yes things are going good here in northern Manitoba, days are getting longer and spring is almost in the air.

Would love to show the saws but everything is disassembled and parts are getting their final work over and polish before assembly.
It's been quite an adventure with this project for the last 18 months or so.

Looking forward to future adventures in competitions throughout North America making everything worthwhile.

[Tacotodd]

The next thing that you'll be telling US about is the 4-stroke hot saw that your building. You know, the one that runs a 1/2" chain pitch 😳 Boy, wouldn't THAT be interesting. You'd have to specially modify the chain just to keep from a DQ before you even started the first cut. If it's got enough torque, I don't see why you couldn't just take the depth gauges down real low and then modify the rest of the chain like in a normal competition saw, but be able to take so much wood in a single pass that you would be winning every event with that sucker! 🤷‍♂️

[HolmenTree]

Latest 4 stroke technology is impressive but for a hotsaw the extra weight is a no go.
For a hot start(engine already running)and a single cut in a 30" diameter log it can have potential alright.
But cold start with multiple upwards and downwards cuts nothing beats a 2 stroke.

You can have all the horsepower and the best running hotsaw in the world but the other 50% success rate totally depends on how the sawchain is setup and sharpened.
The #1 sawchain part that needs the most attention is the depth gauge clearance setting and profile.
#2 the chisel bit profile with cutting edge angles. 
In North America Stihl Timbersports qualifying competitions you have basically three species of wood to fine tune your chain for....soft pine, poplar and tough Douglas fir.

When you get that chain all sorted out it then needs to match the gear ratio diameter of the drive sprocket for the size and species of wood....with a percentage of moisture content and fiber density thrown in. :D

That's just the success rate for the saw, the other 100% relies on the operator.  

[HolmenTree]

So 12 years ago I bought this abrasive blasting cabinet to help  restore vintage chainsaws.

Well I'm using it for the first time this year and I'm not doing vintage chainsaw restoration.  :D

#3 crushed glass sure strips the motorcycle parts nicely of tough paint.
Going to finish them off with #7 glass bead to give them some shine cleaning them up nicely.

[HolmenTree]

Sorry guys I forgot about my hotsaw thread over here. Last posted 6 months ago.

So update,  my tree service season will be winding down for the year after Halloween.
Then it's back into the shop getting these hotsaws up and running for testing. The YZ125 and CR250R cases and cylinders are bead blasted up nicely for painting,  then it's onto assembly.
I'm leaving the CR500R parts in its bin until later in the winter, maybe sooner.

Here's the engine's on display in first pic. Spare cylinders and heads for the YZ125 and CR250.
Last pic is a 7"×12" mini lathe I just bought. I should have had one of these ages ago.
90% of the turning and milling will be working on aluminum. With lots of smaller jobs I can do myself.

 


 

[HolmenTree]

These are the YZ125 and CR250R cylinders, heads, cases, ignitions and carbs



 

[olcowhand]

Willard, I missed you (on this thread)....
Steve

[HolmenTree]

Willard, I missed you (on this thread)....
Steve

Hello Steve, 
yes it's time I get back to it as I always like to say   I never hope to leave a job without finishing. 
I can't wait to get these bad boys in the wood.