Setting up a Beetle with a YS60 FR - can anyone kindly share the best length from the glowplug (center of exhaust) to the first baffle thats currently running or has experience with a YS 60 short stroke with a Hatori header and pipe ?

Appreciate any replies,

Dan

You are better off tuning it yourself. Prop, fuel, engine condition (New, not broke in or used), type of tuned pipe , etc.... all plays a roll in how to set the best pipe length for your particular engine. It is not hard to do! Just take your time and take small steps.

Hi Dan,
If you have an Hatori 605 pipe (short stroke pipe) I'd start at 14.5" to the first baffle if you plan to run a high rpm prop (11x7 or 11x8). If you wan to run a larger prop (11x11, 12x10) then I'd pull the pipe out to 16.5". As long as the engine is rich enough and the pipe is long enough then you will maintain rpm in sustained verticals. If not (and the engine is not going lean) then pull the pipe out another 1/2".
Good luck,
Will

Thanks for the replys.

Will thanks for the PM yesterday really appreciate your advice. The pipe is the Hatori 605 pipe and matching header for the MK Beetle.

I know you can go slow and take a bit off at a time, but its nice to have a reference (like with the MACS charts) however under the normal hatori pattern setup for this motor (ie; 605 pipe, 11x7 - 11x8 apc prop, 15-20 % nitro, etc....) there has to be a ton of experience on this motor. Will's advice is the type I was looking for reference.

Beetle is the classic that I purchased last year from RustyB. Great guy and a great plane - looking forward to getting her finally going in the next week or so.

Here's a reference guide coming from Golden Gate Hobbies for both YS45 and 60.

Thanks for the charts ! great information to have.

Anyone have a Hatori 650 or 601 and can give me the measurement of pipe ?

Really not sure which I have. I have two, one was on a YS 61 long and 1 was on a .60 FR short,
both pipes are identical and measure 17" from end to end of pipe.

Thanks again for the help......

Hey niteman,
I use 10% sig fuel, apc 11-9 and cut my manifolds to 4 inches.

that is a great starting point and we are same in altitude.



BTW I haven't forgot you on that one plane we talked about.

Dave

That's a beautiful Beetle, Dan!!

Thanks Will,

The plane really is extremely well constructed and finished. Wish I had the skill-set and patience to build one of these MK classics. I'm afraid we all have gifts in life and mine is not fine model building - ARF's OK, but not stick building etc...

I could have took the easy road and left the std. YS .61 in there that came with the plane or changed it out to one of the AR's I have which I believe would be correct for this period and plane, however I love the sound of short stroke on the pipe - reminds me of when I was a kid starting out in pattern - thats all there was.

The modifications are not a big deal to fit the YS 60 FR and header pipe, just a little time consuming to get it right. Also the grass field that I fly on makes it really tough to swing a 12" prop without mowing the lawn. May even have to try a 10x10 to 10x12 apc to get ground clearance. Pavement is a good hour and half away !

The only problem I am having is identifying the Hatori pipe I have - it measures aprox. 17" from end to end which I believe rules it out as a Hatori 601 and makes it either a 650 or 700. Its the old style smooth tapered finish no ribs or bumps where there are baffles. Hopefully someone can definitely state exactly what the end to end length is for each of the popular Hatori pipes (ie 601, 650, and 700).

I did find some information on line, but there are some conflicts in the numbers - note the 700 length dimensions differ.

Any help is appreciated. Attached are a couple of picss with sizes, but need clarification or confirmation of the same.

I agree with you 100% not every single engine with pipe is tuned the same way.

Here is a step by step guide how to do it.


Attach the header at its full length, with the silicone coupler and the pipe. The front end of the pipe should be about 1 mm from the rear end of the header, with no contact.
Any length within the coupling is an integral part of the 'tuned
length'.
Firmly attach the tuned-pipe, so it is not blown back by its own
pressure waves...

1. Open the high-speed needle 1 turn from the last no-pipe running
position and start the engine.

2. Adjust the high-speed needle at full-throttle, for the highest RPM
(without any sagging). Write down the RPM! Don't remember it, just write it.

3. ***Make sure that if you close the throttle to idle and then open it again, the engine returns to the same top RPM it had achieved! This must happen without you having to 'pinch' the fuel-line, or to touch the needle again.

4. Shut the engine down, remove the tuned-pipe and coupler and using
the tubing cutter, remove 5 mm off the rear of the header.

5. Keep the piece you just cut and de-burr the end of the header, so it is smooth, with no shavings, or flow obstructions.

6. Reassemble everything, pushing the tuned-pipe forward the header,
until they are again 1 mm apart. Repeat from '1' and again note and write down the RPM. It should be higher than it was earlier. It could only be slightly higher. Make sure '3' occurs! It is one of the criteria that can determine that you are done.

If the RPM is not increased after the last cutting and/or the engine
will not return to the same RPM, upon opening the throttle from idle to full (meaning it has become too short), you are basically done!
Insert the last piece of tubing you have cut off the header, into middle of the silicone coupler and reassemble the header, coupler and pipe.

Dan,

a 17" pipe is pretty long (700 series) and I doubt it will be well suited to a short stroke FR if that's what you want to use. If in addition you are planning to turn 10" props, keep that pipe for the AR's. You'll want a shorter 600 series pipe or a Macs 10cc short stroke.

Oh, you hinted at the idea of cutting the pipe. Don't cut the pipe, cut the header. But you know that no doubt.

Beautiful Beetle BTW! You must be Rusty's famous client...

David

Thanks for the replies and tuning information. I've tuned these types of motors before little at at a time, but appreciate the refresher coarse.

Dave, your right pipe is too long - I'll order the right one. Famous client LOL, just a broke client at this point !

Hi Dan,
I think you have enough information, if not just send me a round trip ticket and I'll make a 'house call' .
The original Beetle was powered with the YS short stroke (as was the original Aurora). The YS long stroke came out very late in the '80s (and the AR, not until the early '90s). The YS 60FR responds very well to long pipes and larger props as it has a very flat torque curve. Ivan Kristensen ran the YS 60FR in his Summit series very successfully.
As for grass runways and the Beetle, try an 11x11 or 11x10.
Good Luck!
-Will

Will hit the numbers for the YS60 short stroke on the nose. Exactly where I ran mine, earlier with small props and then later with the larger loads. Used to burn 15% glow fuel in mine and a 12x11 or 12x12 apc.

The short stroke YS was the best 2 stroke engine they made in my opinion. Wonderfull field manners, power to burn, terrific mid range response, tick over idle...what else is there?

Here's a picture of my Hatori 601 and 650 pipe. The 601 measures 17" overall length, while the 650 is 18- 7/8" long.

Thanks Ferio for the pictures.

Little confused now. I thought after looking at the information I and others posted that the Hatori 650 TUNED PIPE 60L (LONG) was supposed to be aprox. 15"+ long and the 700 pipe is 17"+ long or so as shown above. I also thought the 601 was the shortest chambered pipe in the group for short stoke .60's and high rpm props and measured 15"+. Perhaps I am missing something here. Did they change the overall length or length to the first chamber when they went to the ribbed style finish vs the older smooth ?

My pipes are the non-ribbed smooth pipes like Ferio posted. Wish I had an older and newer Hatori catalog with exact spec's to have for reference - can't find online. Anyone have a pdf. version with pictures and specifications of these pipes ?


Attached is a pic from an ad I found showing a guy selling a Hatori 650 pipe with his Hanno, doesn't look like Ferio's above more like the 15" spec I thought it was - only a picture however. I have a hatori that looks just like the one in the ad and measures 15-1/4" (confusing). Just search Hatori 650 and the ad will come up.

Also the other pic is the 700 pipe and specs right from HatoriUSA website and the pipe is 17" long.........