Just to let the people know that have been on the look out for me a Monark I purchaed one today. Long time finding a complete bike. A close Friend decided to turn loose of his and called. Thanks to everyone who went the extra mile to try and find one for me.:)
Ron Carbaugh
Ron,
Monarks never had a "D" engine, the "D" engine came out after Monark had died. Some Monarks had "B/GS" engines.
I don't know everything, but that's what I believe is true, I was wrong once before.
Bob
Bob,
You were never wrong!?!?!!?!?!?!?!
I have heard that there are a few Monarks with D Motors in them. I don't know if they came that way or not, but check out this web site:
http://www.varberg.se/~igro/index.html
There is a registration page with bikes with D motors.
Donny Smith
Hi Donny, I was reading your post with great interest. I looked at the ISDT Monark in the picture. I counted the fins on the cylinder and counted 7 instead of 6 like on my "D" model motor.
I was not aware that the "D" model motor came with a 7 fin barrel... I guess it's back to the drawing board for me. I'm trying to learn as much as I can about the Pentons/Sachs and Monarks.
I'm also looking for a 175 Sachs motor for my cross-country project this winter.
Dirk Williams
Dirk,
I looked at that too, and to the best of my knowledge the D cylinders ALL have 6 fins. I have tried to ask, but have not gotten a reply. It is my understanding now that the Monark did NOT come with a D GS Pro, but maybe with a D GS motor. As you may know, Monark with the B motors used a Sachs standard part for the MX and a different GS part number for the parts for the GS and then only used a Monark parts number for the GS Pro. It's so confusing!
Donny Smith
Thank you Donny, I'm learning. I just read something else that kinda strikes me as odd. In the porting specs from Mark Holloways' Monark page I read that if you do the GS porting that you have to use a special GS Piston.
The article states that the rings are pinned differently then the stock Sachs. which I read to say won't hang up in the widened ports. Any knowledge on this. I'm wondering what exactly the difference is and where do you find the GS pistons. Will the mentioned GS piston work in a stock barrel.
Dirk Williams
Thank you Donny, I'm learning. I just read something else that kinda strikes me as odd. In the porting specs from Mark Holloways' Monark page I read that if you do the GS porting that you have to use a special GS Piston.
The article states that the rings are pinned differently then the stock Sachs. which I read to say won't hang up in the widened ports. Any knowledge on this. I'm wondering what exactly the difference is and where do you find the GS pistons. Will the mentioned GS piston work in a stock barrel.
Dirk Williams
Dirk,
The Monark GS piston part numbers are as follows:
54 mm = 0686 207 035
54.5 = 0686 207 036
55 = 0686 207 037
55.5 = 0686 207 038
The standard Monark pistons are
54 mm = 0686 207 025
and so on.
The GS had different part numbers for the head and cylinder as well. The GS Pro used different head and cylinder but had a special Monark (MCB) Part number.
Wish I had of paid more attention to this back in the day when I was working on these things.
Donny
Donny Smith
Rob,
Lets just say you are right about the Monark/D engine comment. All I will say is when all the smoke clears there will be some Monarks turn up with D engines. Now to further the problem I can't say what, when or how these engines ended up in Monarks, but as we all know manufactures always have something in the works and will use it in the case of needing to win or help (in this case) a factory stay alive.
Just my thoughts and I have been wrong before, but at least WE air this history out for everyone to share and who is right or wrong isn't a issue with me. Thanks Rob for you great input[^].
Ron Carbaugh
Thank you Donny. Any idea where to get GS pistons, I have 10 or so Wisco Sachs pistons, I wonder if they are made both ways. I'll have to dig them out and see.
I do have one barrel that has been "worm ported, with the extra ports being right below the rings at the rear side of the barrel". The barrel was semi-ported, however the port work is very sloppy and needs some finese, the piston is .60 over Wisco.
Dirk
Dirk,
On the subject of pistons all one has to do is be sure that rings wonn't hang up in the ports. If you have a cylinder that has this problem and you can't find the proper piston all you have to do is reposition the pin that positions the ring(s). A good machinist can handle this job or if you have a drill press you can do it yourself.
The "worm ports" should have no bearing on the ring positioning because of its location.
Ron Carbaugh
Please explain the proceedure regarding the re-pinnng of the piston. I'm capable of some things, however I have never done this or even thought about reloacting a piston ring-pin.
How does the existing pin come out. How is the existing hole filled . How does the pin stay in place after relocation, I'm assuming you use the same pin taken out of the origional ring-pin location.
Sorry to ask these questions. My guess is that most of us haven't even thought about this kind of stuff before. Please educate me/us.
Thank you.
Dirk Williams
Dirk,
Hopefully Ron will pipe in here soon. I have never done it myslef, but have heard of it being done before so that you could use Sachs cast piston in the aluminum and aluminum in the cast. Kip Kern told me about this awhile back.
I have not seen any GS pistons anywhere and don't know if that was the only difference between them. I wonder if there is any difference in the transfer port openings? But if there were, that could be easily corrected.
Donny Smith
The rest of the story is that I had Bill Cappel's GS Monark bored for him. We purchase Sachs pistons from Alan B, and used one in the bike.
Went together no worries, Added a 32 Mikuni, an Internal Rotor PVL and the bike fired on the second kick. Bill rode the bike about 10 minutes with nothing unusual happening. I'm sure the Barrel was a GS barrel as the porting was a work of art, and measured out proper for a GS. The only measurment that was questionable was the spigot? which was opened up, but not to 28 or 29mm.
Anyway I did not cut the intake side piston skirt to change the port timing, and was honestly unaware of two different style pistons. I'm guessing that lots of us are running GS ported bikes with stock pistons. I want to get it right the first time, not after trashing Bike's.
I spoke with Allen B earlier today. He was also unclear on the two kinds of pistons. If someone has both kinds of pistons "GS and Regular" could you measure the ring pin differences and share them with the rest of us un-informed guys.
Sorry to be a pain in the ass.
Dirk
Dirk,
I am not sure there is a problem running the regular Sachs piston in a GS ported cylinder. I have my own porting specs and have never used/measured the porting specs on a GS engine. Unless the ports are elongated into where the ring pins are located there should be no problem.
On to the pins. Taking them out normally requires very strong and small needle nose to try and move it so it will come out. Sometimes you get lucky(I am talking about all brands of pistons now) and the pin holes are in the inside of the piston where you can force the pins out from the inside out. I have mostly used the same pin going back end except where piston manufactures (Honda) would send me new pins. Just drill the new hole(position) undersize and gently force it in the new hole.
Please don't everyone start trying this and ruin perfectly good pistons. It is just a old trick we used in the past when we had to do so much R & D on our own. OK OK[:p].
Ron Carbaugh
Thank you Ron. I try and learn something everyday. In reviewng my port spec diagram, I see that the intake ports are angled and the statement is attached. " All port width diameters are "CHARDAL"
I have no real idea what that means,I think it means tapered of some sort. If I had a dictionary I would look the word up. I'm a Public servant not a machinist.
I also have a stock barrel and piston out it seems to measure loosley alright. At most we are talking 2mm to 3mm in porting it dosn't appear to be a danger. Or am I looking at it wrong.
Dirk
Dirk,
The word is probably chamfer. It just means beveled or rounded off. The 2 0r 3mm is fine(if you are talking looking down the barrel(or cylinder). I hope this helps and as always I am sure some expert will correct me if I am wrong[B)].
Ron Carbaugh
OK definition of "Chordal" via the computer dictionary is "A musical note", "In harmony with". nothing to do with a term for measurment or a machinist application. Next I'll be singing Combyya in harmony with my two black labs.
Cappy need your help on this one, what does Chordal mean. Gotta be German or Swedish and your in Germany.
Dirk
OK,OK, per my machinist uncle I'm screwed up. A straight line connecting to points on a curve, is the real meaning. A math term.
Dirk
Dirk,
Thanks for the new word. I will check with my Machinist Father to see if he has ever used this term. Just never crossed my books or terminology. Good to learn something new. Signing off on this subject................[:p].
Ron Carbaugh
Dirk, we have a guy out here in funny California that is a machinist/engine builder and he claims that "Your engine is my spiritual journey". So you never now when your engine builder might be in "Harmony" with your porting specs. I have an uncut NOS monark six fin cylinder that is no different than the regular old seven fin, spigot mounted carb, Penton 6/B cylinder. The ports are all in the same place. The only thing that is different is the carb mount. Someone once told me that he had a GS pro sleeve that he would let me take a tracing of, but he sold his inventory and I don't know if he still has it. The fact is that if you port the cylinder to the moon only the best experts can run the machine wide open all the time. The bike becomes much harder to ride and keep on the pipe for the average rider. As to the question about relocating the ring pins. The reason to do this is if you widen the tranfer ports. The problem in doing this is that if you widen the port in the cylinder you should also widen the port in the aluminum too. The problem with that is you only have so much metal to remove before you have a hole to the outside of the barrel. Now you could cut all the fins off, add metal to the area, revmove even more metal out, and then reweld the fins back on. The whole thing is that the barrel can only get so much of a fuel charge through the small transfer ports. The best way to get more of a fuel charge is to add a bost port. There are two ways to do this. First is to remove the liner and cut the bost passage behind the outside of the liner in the aluminum that leeds up to some kind of a window in the liner. I'm not sure about how this works, as I've not seen it done. The other way I've not seen either but it's supposed to be possible to run the bost charge up the inside of the cylinder wall between the piston and the cylinder. Must be a groove running right up the inside of the cylinder. OK time for the experts to give their two cents. I'm probably going to run a stock 5/A motor this year, it gets me around the track just fine. I find that if I set the piston up with a minumun clearance .0015 and rings gaped at .003 These engines have just enough midrange power to get you out of trouble when I make a mistake, or miss a shift on the track. If you mess up on the B motor that's fully ported you better drop down two gears to get going again. Buy the time you do that you've been passed by several bikes that don't miss shifts. So the storie goes, get your shifting right, keep your top end fresh, and hope you never miss a shift.! G man.
Go easy folks .
2 or 3mm more in port height or width is a very great difference. If i figured this right , 54 mm is 180 degrees so 2 mm is a change of 6.6666 degrees in port timing. Rule of thumb back when for port width was a max of 65 % on any port width on a 54 mm bore thats 35.1 mm? so be careful folks.
Chordal is a math term.
I picked this off a web page with math definitions
Chord- A line segment that connects two points on a curve.
Here is part of an article from EC Birt that will help explain it some.
http://autos.groups.yahoo.com/group/PentonRestorationandTechGroup/files/Chordal%20port%20measurement/
It looks like it is the width of the port measured with the cylinder opened up and laid flat. I think You can use a stiff piece of paper lay it against the inside of the cylinder and do a rubbing with a soft pencil. Lay that out flat on a table and you should have your measurement in MM or Inches.
Ron , Doug am i missing anything with this? If im wrong some one please shoot me down , chuckle chuckle. One could make some very expensive mistakes porting a cylinder with out the right base line knowledge.
John D.
John,
I don't think you are missing anything except this porting bazaar could go on forever and then we are back to what type of oil do you think is best for a 2 stroke??? Take a hint from Gavin and unless you are a expert try running stock with a great pipe(mid range) and one would be surprised how fast of lap times you can turn. The really fast bikes can only be ridden VERY FEW people.
chardal........chordal..........chord all we are doing are simple drawings of port layout on a flat piece of paper***simple***
I like the last thing Larry Perkins told me when I picked up his Championship 100 Penton "be careful on the first time around the track it is difficult to ride and is VERY on/off type power. He was/is right. But it is Fast. Going to bed...thanks for all the fun:).
Ron Carbaugh
Thanks fella's, I have a clear understanding of the word, the meaning and the theory.I only know a couple of ways to learn and that is read the subject matter, and ask questions of those who are the experts.
I was a pain in the ass in school aswell. I live in a world where we always ask. Who,what,where,when,why and how. nuff said !
Dirk
Ron, I see your bidding on the Banke down pipe. I've often wanted to try a down pipe on my six day, but they are very rare. If you succeed in winning the bidding on the down pipe it would be cool if you could take some measurements for purpuse of comparison and post it for the pipe building gurus. Just a thought. I was going to bid on it but when I saw it was you I left it alone. Gavin.
Quotequote:Originally posted by Bryson Williams
I'm also looking for a 175 Sachs motor for my cross-country project this winter.
Dirk Williams
You are aware that the 6 speed 175 Sachs engine pistons are non existant. In Germany they replace all the 175 Sachs engines with 125s.
I have 2 175 Hercules GS175/6a and one 175/6a engine and one spare piston. NO, you can't have them. You can put a early Jackpiner topend on a 125 Sachs lower though. You have to modify the pipe to fit. John Durril did one.
Dwight
Dwight Rudder
7 time ISDT / E medalist
8 time National Enduro Class Champion.
Gavin,
Thanks for the "nice guy" note. If I do win it I will be happy to take it over to Kevin at Circle F pipes and let him copy it for you. He does nice work and is reasonable. He has been at pipe building for many many years. You can email me directly. I will probably take a bike over there so the fit is right on. What year Penton are you looking at putting it on?:)
Ron Carbaugh
Donny,
Did the stock Monark pistons have a hole above the wristpin hole that was larger than the wristpin hole and went all the way through the piston? Included with some Tyran items are pistons with "superlite" written on the box with part number 0686 207 025, the 54.0mm size is crossed off and written in is the correct piston size, 54.93. I haven't run into anyone yet who knew of the "superlite" Sachs pistons, maybe they were stock on the Monarks.
Thanks
Paul
Paul,
None of the Monark Piston I ever saw had a hole like you talked about. I did have a Jackpiner Piston with a longated hole above the wrist pin, but it didn't go all the way through.
Donny Smith
Dwights answer is the reason we did the KTM top end swap instead of a 175/6 Sachs top end on my 175.
The 175/6 Sachs use a 60 mm piston and a 61 mm stroke. The 60 mm size was the problem. we were unable to find any pistons that would work as a replacement. At one time Yamaha made a bike ( twin) that had a piston that would work with some changes for making an alloy cylinder 125 a 152cc engine ( it had a 14 mm wristpin)
Those pistons are very hard to find.Thats what the 152 kit piston from Wiesco was based on. None of those pistons would work on a 175/6 Sachs. The wristpin size is way too small and the piston crown to top of piston measurement is way off.
If someone has a new run of 175/6 pistons made up then with a lot of money you could make 175/6 from a 125 A engine.
hope this was some help
John D.
Hmmmm, so I guess I'm not looking for a 175 Sachs. I do have one running jackpiner," Has lights on it" and two 175 motors some guys in Washington state gave me in trade for 2 125 Penton frames. " They made Penda's" What Engine # would I need, to do the 175 Penton top end swap, to the 125 Sachs.
How much bigger is the header pipe on the 175 then the 125.
I have two Sachs pistons that are forged, and have a machined hole above the wrist pin holes, Somehow they got put into my Cr Honda 125m piston drawer. Are these perhaps the GS piston I was bugging you guys about?
Dirk
Dirk,
You can do the 175 swap with either an A or B engine. I would use the A motor for a smoother power delivery. Its easier on the clutch and gears. You can use the old , long piston 175 cylinder and head or the 76/77 new short piston cylinder and head. Both have their advantages and dis-advantages.
The pipe header diameter depends on which cylinder you would use.
The old long piston cylinder uses a larger head pipe diameter than the short piston cylinder.
What year frame would you want to put the engine in? The 76/77 and up pipe is not a good fit in the 72-75 Six-Day frame. We used a 72-75 Jackpiner pipe and modified it to fit after trying to install the 77 175 pipe first.
We went with the new short piston cylinder because at the time the long pistons were very hard to get and the 77 cylinder used a liner that could be removed when modifying the cylinder. We then had to open up the exhaust port diameter between the where it exits the cylinder and meets the pipe. Blending it back towards the piston from the exhaust flange about 3/4 of an inch to let us use the old style Piner pipe.
How serious are you in doing this? The reason We went with the swap is the 125/175/5 or 6 speed is about 30 lbs lighter than a stock Piner. BUT big BUT here, you give up strength in doing the conversion. Haveing said that Monark use the 175 KTM top end bikes to win medals in the ISDT so they can do the job. The 5/6 speed Sachs engine is an old friend to me. I'm not hard on gearboxes , have never had one fail on me. We use the bike for the Reunion Ride and some fast trail rides 25 to 60 miles long 5 or 6 times a year with Rick G.
The engine cases need to be opend up to recieve the 175 cylinder. The bottom of the cylinder liner would need to be shortened probly and reshaped. If you use the tall cylinder you would need the cases machined down where the base gasket sits to get a base gasket seal and set the piston in the right place in relation to the rod length and piston crown height.
Ill be glad to go over step by step what we had to do if you would like.
John D.
I just returned from Medford Oregon, where I picked up a Pention/KTM. Has a blue tank, layed down rear marazocci shocks, leading axle marzocci front shocks has six fins on the barrel and a bing 54 carb.
This bike is stuck, I paid 185.00 for it. The tank is a smaller version of the green tanks and the blue tank on my Jackpiner. was looking for the engine,"75210145" Did I do good what the heck is it?
I was told it's a 175 is it the right barrel for this project.
Dirk
Dirk,
Here is a shortcut to some pictures of my engine.
Are you thinking about building a Sachs/ KTM 175 6A or 6 B? Whats the engine #?
http://pg.photos.yahoo.com/ph/sachs175/album?.dir=/1a95
John D.
I thought a 175 engine in a Sachs would be cool. A 175 in one of my Monarks would be even cooler. So yes, I am really thinking about building one. While I was over the hill I checked out the 1974 Penton 125 "D" model motor. Not a GS still a very clean bike. I offered 1200.00 for the bike.
The Penton/KTM I just purchased would be a cool bike to rebuild. I need to check the engine #'s I have on the two 175 motors I have in my shed. I would hate to rob the top end off of this KTM, if the other motors top ends will work. I do remember that the two motors are Black in color. Can't do that until tomorrow.
Dirk
Dirk,
The older black engine cylinder is what Monark first used. Use the base gasket off one of them and lay it on the 125 cases. That will give you an idea how you need to go.
We will try and get some digital pictures of my engine cases apart so you can se what will need to be done. You need to find a machinist that can do this work. Everything needs to be cut on the same plane as the stock 125 . The cases will have to be opened up with out messing up the center case gasket sealing area where the cylinder goes in. Same with the base gasket area. It will need to be machined down some. The A cases and crank would be a better choice I believe. Did the pictures help any?
John D.
John I do have two 125 early Penton Fan head motors aswell. Are you recommending that I use that lower end rather then a Monark B motor?
Dirk
Dirk,
I wouldnt use the D GS cases. They are easy to tell apart from a B or A set. Doug told me last year that the reason Pentons didnt come with the stuffed cases is the crank ( I think it was the Rod) didnt give the relability at sustained high RPM,s . Long straights , desert races , ISDT, that was needed.
I would use a set of 6A cases. The B crank is lighter and would pick revs up quicker but that would put more load on the crank, clutch and gears. As a 175 the engine will put out a lot more torque than as a 125. I think the A crank is 1 and 1/2 lbs heavier than the B. That will smooth out the power delivery and give the drive train some relief.
Look at the pictures in the folder. The transfer port area of the cases will need to be matched to the cylinder. The cases you use should have the metal already cast for you to make them as large as mine are. Then you will have to make the cylinder match the cases.
We had to find someone to weld up the back transfers for things to fit ( look at the pictures).
My cylinder is 3.575 from head gasket surface to base gasket surface. I did not have to mill down my cases with the 6 fin cylinder just use a 1/64 inch base gasket to get my deck height right.
once you get the cases opened up and the cylinder spigot trimmed to fit you can slide it on and see how much will need to be milled off the base gasket area of the cases.
The tall cylinder transfer ports line up a lot better with my cases than the short cylinder. With Al now haveing tall pistons in different sizes in stock and someone to reline worn cyliders I would use the tall , 72-75 cylinder. I dont think i can go much over 64.25 mm on bore size so i will reline the cylinder after 2nd over is worn out. The 72-75 pipe fits the Six-Day frame with just a little modification also so the 72-75 cylinder and head would be my first choice on a set of 6A cases and A crank and a 72 or 73 175 pipe.
John D.
Dirk,
Here is a short cut to my photo album. it has 2 folders with pictures of the engine cases, cylinder base and how we did a 12 spring clutch to handle the added torque of the 175.
http://pg.photos.yahoo.com/ph/sachs175/my_photos
Let me know if you can view them and if they help any please.
I have the files in the photo section of the library also folks.
John D.
John after giving this project very careful consideration I'm wondering if I have the skills to get it done. I do have a set of Sachs cases with a Crank in them. I will take them to a machinist friend and see if he is capable of doing the work.
I'm not having any luck in locating the sites your posting. I read that it would also be best to upgrade the clutch as well. Hmmmmmmmm. I am chasing a Sachs 175 lower end in Reno Nevada.
Dirk
John, I was able to access the photos. WOW that bike is fantastic. I'm going to give it a go as my winter project. I'll contact Charlie Brown to see what a new sleeve will cost. Is that an Letron carb on your bike. I have what I believe is a 36 or 38mm letron carb in a box. The carb came with some pumper carbs I was given several years back.
I think I'll ask Charlie Brown do the machine work on the cases as well.
Thank you. Dirk
Dirk,
If you have a long piston 175 cylinder that is Std or 1st over with a good bore you wouldnt need a sleeve. Al has cylinders with sleeves installed on an exchange bases now in stock. The cylinder in the pictures is a KTM 76/77 175 cylinder not a Sachs 125 with a big bore kit.
Use the pictures as a guide. Everything you guys do will be a little different than mine. The cutout for the cylinder spigot is max on my cases dont go any larger than mine. Take a stock 125 case half with the crank, piston and cylinder installed on it. Rotate the whole thing through a complete cycle. The piston will come out of the cylinder at the bottom of the stroke a good bit. I would keep that to a min. on the 175 cylinder. I think you will have to shorten the liner at the bottom some to have it fit . The piston may then come out at the bottom of the stroke on the long piston 175 cylinder . We had to cut the short piston cylinder about .120 inches at the bottom and then tapered the od to fit the cases.
Yes the carb is a Lectron but a 30 mm. 30 mm Bings or an Amal is what came stock on the early Jackpiner. You dont need more power than what came stock on the Piner . You could have hand grenade on you hands if you are not prudent.[V] chuckle chuckle!!!!!
A 30 mm Bing or Mikuni would be my choice for a carb. If anything comes up e-mail me or post it on the board. Measure every thing twice and think about any changes you make long and hard. Its easy to remove metal but very hard to put it back on [:p]
John D.
Note to all.
The D motor was a 1974 engine and Monark was around thru 1976. On the Monark I mentionrd a couple years ago, there are at least 6 listed with D motors.
Now a new question, what is a 1251/E motor????
Donny Smith
Paragould, AR
Hi Donny,
the 1251/5 E MC was the last version of the MC engine until 1975.
Best regards
Guenther Vogt,
Hercules Club, Germany
******************************
Hercules-Interessengemeinschaft e.V.
URL: http://www.herculesig.de
******************************