TRX250R chainsaw

[BigMoneyGrip]

I will defer to the experts but, I would think that applying "limited modified" type rules and alcohol fuel to a saw engine would very probably yield a 3x increase in power. There is no need to triple the rpm of a 2-stroke, to achieve the desired power level, in most cases.

I would bet that you can't. The alcohol doesn't do a whole lot for power. I agree with the RPM part.

I wasn't saying that he needed to source out for parts. I was giving him a heads up on some cool stuff. I always like to know what my options are and not be limited to one thing.

The reason I mentioned the Briggs stuff was because I thought there might be another common ground. I'm not putting words in his mouth like you are to me. I'm trying to offer other ideas not not busting chops.

I'm done. You can win this one.

 

[parrisw]

And my point is that you took the time to post in a man's thread, a man who has quite a skillset based on what I have seen, and told him to send his money to another engine builder. Then, you start rattling on about Briggs parts.

I will defer to the experts but, I would think that applying "limited modified" type rules and alcohol fuel to a saw engine would very probably yield a 3x increase in power. There is no need to triple the rpm of a 2-stroke, to achieve the desired power level, in most cases.

Here's my other point, I think Frank is going to build a kickass saw. No need for him to send parts anywhere or have someone else do the work.

I would bet that you can't. The alcohol doesn't do a whole lot for power. I agree with the RPM part.

I wasn't saying that he needed to source out for parts. I was giving him a heads up on some cool stuff. I always like to know what my options are and not be limited to one thing.

The reason I mentioned the Briggs stuff was because I thought there might be another common ground. I'm not putting words in his mouth like you are to me. I'm trying to offer other ideas not not busting chops.

I'm done. You can win this one.

Guys, why don't you start your own thread about your dumb argument, or better yet take it to PM's, I'm sure I'm not speaking for myself here, that its not wanted in here. Far too many threads have been ruined lately from BS like this.

 

[thomas1]

Guys, why don't you start your own thread about your dumb argument, or better yet take it to PM's, I'm sure I'm not speaking for myself here, that its not wanted in here. Far too many threads have been ruined lately from BS like this.

Done and done and agreed. My end of the mess will be cleaned up momentarily, I would bet the other side will as well, if he hasn't already. My apologies to Frank and everyone else.

I couldn't edit/delete my first post? Maybe because it was "liked"? Brad can you "unlike" it and I will see try to modify it.

 

[parrisw]

Done and done and agreed. My end of the mess will be cleaned up momentarily, I would bet the other side will as well, if he hasn't already. My apologies to Frank and everyone else.

I couldn't edit/delete my first post? Maybe because it was "liked"? Brad can you "unlike" it and I will see try to modify it.

Thanks.. Dam wish it was always that easy.

 

[Eccentric]

The left side case is the costly side. It's the side that gets hammered by the chain when thrown and everybody's looking for one. I bought a set from a guy that was selling the right side and I asked if he still had the left. He did, but the case was broken and not useable. That was just what I was looking for. He gave me the broken case for the cost of shipping and I welded it up to make a good set. I bored the cases to do a stroker 370 Big Bore but put it on the shelf for now. Good Luck finding one cheap.....Hahahahahaha!

A case that's "ruined" for quads and trikes would be fine for you guys. The countershaft area of the case (which get's "holed" by thrown chains) gets cut away when you guys build a saw doesn't it?

Looks like a 87/88 cylinder......85/86 is the better cylinder to work with, because of the intake.

I agree. I raced quads from 1987 to 1992 or so. My '86 TRX250R had more snap than my buddy's '87 (running the same pipe). The '85-'86 engine was used in the ATC's for both years, but in the quad for only one (1986, as that was the first year of the TRX250R and the last year of the ATC250R). That quad was a hoot. I can't imagine running a saw with that engine.:cool2:

 

[thomas1]

A case that's "ruined" for quads and trikes would be fine for you guys. The countershaft area of the case (which get's "holed" by thrown chains) gets cut away when you guys build a saw doesn't it?

Aaron, I think you may have hit on the newest trend on ebay/craigslist. Trashed cases being advertised as "perfect for your bikesaw build".

 

[MechanicMatt]

Hey Frank, when is the expected delivery date on your case halves??? Can't wait to see some work pics:msp_thumbup:

 

[BigMoneyGrip]

I think I have a 38mm Lectron. If I can find it, you can have it. It is set up for alcohol but I have some needles for gas also. I had this on a '86 ATC250R that was setup for dirt drags. I'll look at work Monday and if I locate it, I'll PM you for your address.
These carbs were like a light switch. It was idle or WFO. They didn't work good in between. Should work good for a saw.

 

[Eccentric]

I think I have a 38mm Lectron. If I can find it, you can have it. It is set up for alcohol but I have some needles for gas also. I had this on a '86 ATC250R that was setup for dirt drags. I'll look at work Monday and if I locate it, I'll PM you for your address.
These carbs were like a light switch. It was idle or WFO. They didn't work good in between. Should work good for a saw.

I remember those Lectrons. Some had clear bowls didn't they? The only ones I saw were on alcohol burning sand-drag quads and trikes.

You don't happen to have a 38mm or 36mm roundslide Mikuni laying around do you? I need one for my 75 MX400B.

 

[gink595]

Hey Frank, when is the expected delivery date on your case halves??? Can't wait to see some work pics:msp_thumbup:

Matt, they came in today! I just got home from work so I quickly looked the over and boy were they ever fooked up! I won't feel guilty for cutting the tranny off of this thing.

I think I have a 38mm Lectron. If I can find it, you can have it. It is set up for alcohol but I have some needles for gas also. I had this on a '86 ATC250R that was setup for dirt drags. I'll look at work Monday and if I locate it, I'll PM you for your address.
These carbs were like a light switch. It was idle or WFO. They didn't work good in between. Should work good for a saw.

That's sounds interesting, Thanks! It may end up on alcohol as it is, so it may be a good fit for this! Did you run nitro with that ATC250?

 

[BigMoneyGrip]

Eccentric, these did have the clear bowl. I got hooked up with Paul Gast on these. At the time, I had the only normally aspirated drag bike with Lectrons on alcohol. He ended up tuning these on his pro stock and the sent them to me for final tuning. We eventualy got them and this thing would scream.
I'll look and see about a carb for you. I have several off of old Huskys. Even a Del'Orto from a Cagiva.
Gink, this was on a 250R. I think I can put my hands on it. I'll let you know Monday. The good thing with alcohol is that you can crank the timing up and you can't have enough compression. The ATC had about 15:1. The compression was good for torque and the pipe was good for top end. Overall it made for a good combination.
We tried up to about 25% but the nitro was too finicky. It did sound wicked though. The trouble was getting it to light off. You ended up needing to mix other stuff with it just to get it to burn good. I didn't care fooling with it bit at the time, another friend had a TF Harley and he talked me into it. I'm sure if you had a motor built for it, it would be different. For my combination, it just wasn't worth the hassle.

 

[MechanicMatt]

Frank, are you going to use a harvester bar or a regular bar you have laying around?? I wish I had the tools handy to pull this kinda build off. Please post a ton of pics!!!! My neighbor owns a machine shop, they build mostly 358's for the dirt track boys. I gotta turn him on to chainsaws

 

[parrisw]

I wish I had the tools handy to pull this kinda build off. Please post a ton of pics!!!!

Ya post lots of photo's Frank!! I love to build a bike saw.

 

[Jacob J.]

I guess a Mikuni w/ a pump might be easier. Might be able to use stock boot. Easier to get jetting right. Now that I think about it.

I have a bunch of the stand-alone diaphragm pumps. If you need a couple Frank, you can have 'em, Mikuni and Zama.

I think I have a NIB primer set-up for a Yamaha jet ski if you need that too.

 

[gink595]

Frank, are you going to use a harvester bar or a regular bar you have laying around?? I wish I had the tools handy to pull this kinda build off. Please post a ton of pics!!!! My neighbor owns a machine shop, they build mostly 358's for the dirt track boys. I gotta turn him on to chainsaws

It will probably be a harvester bar. This is all new territory for me as well, so who knows what the final piece could be! This will be a slow going build I imagine as I have lots of stuff to do other than this! My real job don't help that situation either. It will progress though and I'll track the progress with pictures. At this point my focus will be getting the chassis made with trying to keep it light. I have a friend in Indianapolis that does carbon fiber work for indy car, after I figure out what I need for chassis plates they could possible be made from Carbon Fiber where it makes sense. Obviously area's that have alot of torque and high revving chain will probably be more protective! I want this to be easy to handle as the few bikes saws I've seen look terrible awkward to hold with the top handle so high and the rear handle so low. I don't know how achievable this will be but those are the focus points I'm going to look at while doing this...light and ergonomic for what it can be. May turn out to be Lincoln with four fat chicks in it, who knows...LOL

 

[gink595]

Eccentric, these did have the clear bowl. I got hooked up with Paul Gast on these. At the time, I had the only normally aspirated drag bike with Lectrons on alcohol. He ended up tuning these on his pro stock and the sent them to me for final tuning. We eventualy got them and this thing would scream.
I'll look and see about a carb for you. I have several off of old Huskys. Even a Del'Orto from a Cagiva.
Gink, this was on a 250R. I think I can put my hands on it. I'll let you know Monday. The good thing with alcohol is that you can crank the timing up and you can't have enough compression. The ATC had about 15:1. The compression was good for torque and the pipe was good for top end. Overall it made for a good combination.
We tried up to about 25% but the nitro was too finicky. It did sound wicked though. The trouble was getting it to light off. You ended up needing to mix other stuff with it just to get it to burn good. I didn't care fooling with it bit at the time, another friend had a TF Harley and he talked me into it. I'm sure if you had a motor built for it, it would be different. For my combination, it just wasn't worth the hassle.

I'm liking the idea of running it on akcohol with a touch of nitro. I looked up those carbs last night and seen how they are running alky, looks like it is just sucking all it can from a large float bowl, it didn't look like it had any internal jetting...pretty cool concept. I can see why it liked to be WFO, not much jetting for crusing speeds!

 

[atlarge54]

Seems like a guy with about 100 HP worth of chain saws ought to have a woodburner in the shop. At least keep that nice new toy warm.

Kinda chilly this AM----not too windy either.

You better let me see this saw when you get it running.

 

[gink595]

Seems like a guy with about 100 HP worth of chain saws ought to have a woodburner in the shop. At least keep that nice new toy warm.

Kinda chilly this AM----not too windy either.

You better let me see this saw when you get it running.

Hahahaha! That is pretty ironic isn't it! Yeah I should hook one up. I'm going to insulate it this year so that will keep the condensation down. You can come over anytime and check it out!

 

[Trx250r180]

im not positive but i think an 84 atc 250r air cooled cylinder may fit on the cases ,then you dont have to worry about water cooled system and save some weight

 

[thomas1]

Is the heat ever an issue, given the short run times? Does fuel choice mitigate those issues somewhat?