OS or Magnum Carb.......
06-26-2006, 01:26 PM
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OS or Magnum Carb.......
Ok, have been messing around with my Super Tigre G90 for months now. I have had nothing but problems with this carb. I have to keep cleaning it out after about two flights and everything leaks fuel on it even after I replaced all the gaskets. Anyways, have been looking into buying a new carb and after researching on this forum, I noticed some members are using Perry carbs and some are using Magnum carbs on this engine. I have no experience with these carbs. Any one know what would be the easiest to mess with. I know I can put an OS on it but a little pricy for me. Also, which Perry or Magnum will fit this G90?
06-26-2006, 09:12 PM
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RE: OS or Magnum Carb.......
I ran a os 7d from a 1.08 on a st .90 and it worked great
What are the problems you are having with the ST carb if its tuning the S.T. web site has some good info on tuning their carbs
What are the problems you are having with the ST carb if its tuning the S.T. web site has some good info on tuning their carbs
06-26-2006, 09:30 PM
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RE: OS or Magnum Carb.......
ORIGINAL: loughbd
You get what you pay for.
You get what you pay for.
-------------------
All of my Super Tigres run just fine. New and old. Expensive and inexpensive.
Pe Reivers told everyone how to fix the rich midrange in their G2300 Tigres a few years ago. Has it occurred to anyone that the same technique will allow the owner to fine tune the midrange of ANY Super Tigre carb equipped engine?
The lack of willingness to do actual physical work by today's modelers is beyond belief.
06-26-2006, 09:35 PM
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RE: OS or Magnum Carb.......
The 7D would be the ticket if you could find one reasonably priced (check ebay). I'm running a 7L from an OS .61 SF and it's been great- so you're not tied down to a 7D. Typically, I hunt ebay for carbs or, more specifically, engines with the particular carb I may want (I do a lot of mixing and matching- it's a sickness) and toss the engine if it's no good. A friend has a Super Tigre .90 with the Magnum carb and it's performed flawlessly for many years- and is quite a bit cheaper than the OS so I wouldn't turn my nose at a Magnum carb.
06-26-2006, 10:14 PM
#6
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RE: OS or Magnum Carb.......
The standard fix when the Super Tiger 2000, 2300, etc was to dump the stock Carb and replace it with a OS 7D. That was the recommendation from many of the engine writers and gurus as well as the guys that used them.
Use an OS carb and set it once and forget about it.
06-27-2006, 06:49 AM
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RE: OS or Magnum Carb.......
The lack of willingness to do actual physical work by today's modelers is beyond belief.
06-27-2006, 07:35 AM
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RE: OS or Magnum Carb.......
Does the Magnum carb need a spacer or will it fit right in? Also, no one likes Perry carbs? I thought they were good carbs. The carb looks plastic in the picture. Does this make a difference? Thanks......
06-27-2006, 08:44 AM
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RE: OS or Magnum Carb.......
The crankcase hole on my ST90 is 15mm. Both the OS7D and magnum carb. for the 108 have a 15mm neck and will fit right in. Irvine also makes very good carbs if you can buy one, but I am not sure if it is 15mm or not? Other good carbs are webra, moki and the latest MVVS carbs.
06-27-2006, 11:46 AM
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RE: OS or Magnum Carb.......
Ok, found the Magnum 108 carb at this site. Will this slide right in on my Super Tigre G90? thanks.....
http://www.horizonhobby.com/Products...ProdID=ASP9120
http://www.horizonhobby.com/Products...ProdID=ASP9120
06-27-2006, 12:00 PM
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RE: OS or Magnum Carb.......
ORIGINAL: loughbd
The standard fix when the Super Tiger 2000, 2300, etc was to dump the stock Carb and replace it with a OS 7D. That was the recommendation from many of the engine writers and gurus as well as the guys that used them.
Use an OS carb and set it once and forget about it.
The standard fix when the Super Tiger 2000, 2300, etc was to dump the stock Carb and replace it with a OS 7D. That was the recommendation from many of the engine writers and gurus as well as the guys that used them.
Use an OS carb and set it once and forget about it.
------------
If Pe Reivers isn't a Guru, I don't know who is. Surely, not a magazine writer whose only credentials is writing in a magazine. Pe is an engineer.
Yes, you can swap out carbs and that is okay too. But the stock carb is functional and "reprogrammable". Anyone with the gumption to build a model airplane kit - oh - I see. There's the problem. Never mind. <G>
06-27-2006, 12:05 PM
#13
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RE: OS or Magnum Carb.......
ORIGINAL: SamD
IMO, that's a grand generalization. The thought of spending many hours playing around with a carb trying to make it work properly isn't really how I'd like to spend my time- been there, done that, don't need to do it any more. There's this priceless commodity called "time" and as such, I prefer not to let it get away from me, if at all possible.
The lack of willingness to do actual physical work by today's modelers is beyond belief.
------------------
Believe me, I know how precious time is myself. And I agree that a modeler should not have to do this crap on a new engine. BUT! The fix is simple, requires only a few minutes work, once the slot profile is known, and doesn't require special ability or special tools, other than a Mototool.
I tend to crack on folks that don't do things in the old fashioned, traditional way. Why? Because I'm an old fart. Please forgive an old man his failiings.
06-27-2006, 01:50 PM
#14
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RE: OS or Magnum Carb.......
I've been in the hobby over 50 years and NEVER heard of the guy. I was also hobby shack's engine repair guy at the san Diego store for 6 years which kind of makes me a engine "guru". At least they paid me to repair engines which makes me a professional.
I would say that Clarence Lee was a bit more than just a "writer". He was an engine designer (Veco 61, K&B40. Veco 19) and still sells his K&B61 engines through Model Aviation. He was one of the many that recommended replacing the super tigre carb with an OS.
George Aldrich was more than just a writer as was Peter Chinn, Dave Gierke, Harry Higley, and several others whose name doesn't come to mind right now.
Being an engineer doesn't make one an expert on model engines. There are chemical engineers, civil engineers, marine engineers, aeronautical engineers etc. I have several friends who are engineers and work at Boeing and have no clue about making a model airplane engine work and they are areonautical engineers. They have me, the geologist, make their engines work.
By the way, I have NEVER owned a ARF or RTF airplane. Also many guys like to fly not screw around with engines that are a pain to set and use. Does that make them less than someone that can or will screw around with balky engines? I think not.
Old fart?? I'll be 60 next year and have no problem with modern ideas and technology.
I would say that Clarence Lee was a bit more than just a "writer". He was an engine designer (Veco 61, K&B40. Veco 19) and still sells his K&B61 engines through Model Aviation. He was one of the many that recommended replacing the super tigre carb with an OS.
George Aldrich was more than just a writer as was Peter Chinn, Dave Gierke, Harry Higley, and several others whose name doesn't come to mind right now.
Being an engineer doesn't make one an expert on model engines. There are chemical engineers, civil engineers, marine engineers, aeronautical engineers etc. I have several friends who are engineers and work at Boeing and have no clue about making a model airplane engine work and they are areonautical engineers. They have me, the geologist, make their engines work.
By the way, I have NEVER owned a ARF or RTF airplane. Also many guys like to fly not screw around with engines that are a pain to set and use. Does that make them less than someone that can or will screw around with balky engines? I think not.
Old fart?? I'll be 60 next year and have no problem with modern ideas and technology.
06-27-2006, 03:51 PM
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RE: OS or Magnum Carb.......
I ordered a tn2 (twin needle, second generation) carb from Paul at Just Engines for my G90. I gave it a try last weekend and it cleaned up the rich midrange just great. It is relatively cheap (17.95 Euro..... about $38 delivered here to the USA), is a nicely built carb with 2 O-rings on both the high speed and low speed needle. It bolts right on and looks great, even has a front needle valve. It does have a slightly smaller venturi size than the stock ST G90 carb though, and that kind of worried me at first. My worries were short lived though when it throttled cleanly and did not appear to loose much, if anything on the top end. Here's a link the the Jen .91 engine that show a picture of the tn2 carb..... http://www.justengines.unseen.org/Jen_91.htm
I had tried everything I could think of with the stock carb to clean up the midrange including ST's advise of rotating the spray bar also. Anyway I am a happy camper now and that stock carb is history. Another option is the carb off of a Tower .75 engine. It is a bolt on fit also and retains the same large size venturi of the stock ST carb. (maybe too large for good fuel atomization on the G90?)
Ernie
I had tried everything I could think of with the stock carb to clean up the midrange including ST's advise of rotating the spray bar also. Anyway I am a happy camper now and that stock carb is history. Another option is the carb off of a Tower .75 engine. It is a bolt on fit also and retains the same large size venturi of the stock ST carb. (maybe too large for good fuel atomization on the G90?)
Ernie
06-28-2006, 12:24 AM
#16
RE: OS or Magnum Carb.......
ORIGINAL: loughbd
I've been in the hobby over 50 years and NEVER heard of the guy.
I've been in the hobby over 50 years and NEVER heard of the guy.
As for Clarence Lee (if you must quote writers names), up until a few years ago he always said acetone was useless in model fuels. Then he wrote an article in one of those magazines saying he'd changed his mind and that it was a desireable additive. Now, do you think he actually tried it to see for himself and then pass on his findings? No, he read about it on the internet and that was the basis for changing his mind. How do I know he read it on the internet? In the article he mentioned the name of someone who used it with good results. This particular person happens to be a member of my club and I used an article he wrote for our club newsletter as part of my web page that I do for the club.
So that's one example of how a "writer" (and engineer) can get knowledge. I'm kind of proud that my little web page helped an acknowledged expert change his mind but this is the first time I've ever mentioned it. And even though I'm an aircraft engine fitter, gone through all the theory side for 3 years in training and have played with model engines for 40+ years, I'd never go boasting that I'm a "guru"...I realise I don't know everything.
06-28-2006, 02:06 PM
#17
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RE: OS or Magnum Carb.......
ORIGINAL: loughbd
I've been in the hobby over 50 years and NEVER heard of the guy. I was also hobby shack's engine repair guy at the san Diego store for 6 years which kind of makes me a engine "guru". At least they paid me to repair engines which makes me a professional.
I would say that Clarence Lee was a bit more than just a "writer". He was an engine designer (Veco 61, K&B40. Veco 19) and still sells his K&B61 engines through Model Aviation. He was one of the many that recommended replacing the super tigre carb with an OS.
George Aldrich was more than just a writer as was Peter Chinn, Dave Gierke, Harry Higley, and several others whose name doesn't come to mind right now.
Being an engineer doesn't make one an expert on model engines. There are chemical engineers, civil engineers, marine engineers, aeronautical engineers etc. I have several friends who are engineers and work at Boeing and have no clue about making a model airplane engine work and they are areonautical engineers. They have me, the geologist, make their engines work.
By the way, I have NEVER owned a ARF or RTF airplane. Also many guys like to fly not screw around with engines that are a pain to set and use. Does that make them less than someone that can or will screw around with balky engines? I think not.
Old fart?? I'll be 60 next year and have no problem with modern ideas and technology.
I've been in the hobby over 50 years and NEVER heard of the guy. I was also hobby shack's engine repair guy at the san Diego store for 6 years which kind of makes me a engine "guru". At least they paid me to repair engines which makes me a professional.
I would say that Clarence Lee was a bit more than just a "writer". He was an engine designer (Veco 61, K&B40. Veco 19) and still sells his K&B61 engines through Model Aviation. He was one of the many that recommended replacing the super tigre carb with an OS.
George Aldrich was more than just a writer as was Peter Chinn, Dave Gierke, Harry Higley, and several others whose name doesn't come to mind right now.
Being an engineer doesn't make one an expert on model engines. There are chemical engineers, civil engineers, marine engineers, aeronautical engineers etc. I have several friends who are engineers and work at Boeing and have no clue about making a model airplane engine work and they are areonautical engineers. They have me, the geologist, make their engines work.
By the way, I have NEVER owned a ARF or RTF airplane. Also many guys like to fly not screw around with engines that are a pain to set and use. Does that make them less than someone that can or will screw around with balky engines? I think not.
Old fart?? I'll be 60 next year and have no problem with modern ideas and technology.
---------------
Don't be so sensitive, my friend. I'm not picking on you.
Pe Reivers is very well known on RCU and r.c.m.a. I'll bet you would remember him if you saw some of his articles. His best stuff was written several years ago, before his business took off and robbed us of him.
We are fortunate to have you, and many others with great experience, online with us.
***********
I'll be sixty next week, junior. <G>
06-28-2006, 07:08 PM
#18
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RE: OS or Magnum Carb.......
I have had a subscription the RCM, the only magazine Clarence Lee wrote for, since the first issue and I have every copy bound by year. His column was the first thing I read every month. I never saw any mention of acetone in any of his columns. What month and year was this so called mention? I would also beg you to find one person on this country that puts acetone in his fuel. Or who might know Pe whatever his name is.
I haven't been "hiding" anywhere. I have been active in the hobby for over 50 years and was also a member of the commercial side of the hobby. I am friends with many of the big boys in the hobby whom I met either through contests or through my employment at Hobby Shack. RCU isn't what one would call a huge part of model aviation. I post a lot of stuff here but I bet none of your friends ever heard of me.
I emailed several of my friends and club members NONE of them have ever heard of Pe. I guess they have all been hiding too. Funny but EVERYONE of them has heard of Clarence Lee and George Aldrich.
Artisan,
Who said anything about being picked on". You said that because YOU were an old fart you "cracked on people who don't do things the old fashioned way". Well, I'M an old fart and I have NO problems with modern things and modern ways so don't lump all "old farts" together.
I haven't been "hiding" anywhere. I have been active in the hobby for over 50 years and was also a member of the commercial side of the hobby. I am friends with many of the big boys in the hobby whom I met either through contests or through my employment at Hobby Shack. RCU isn't what one would call a huge part of model aviation. I post a lot of stuff here but I bet none of your friends ever heard of me.
I emailed several of my friends and club members NONE of them have ever heard of Pe. I guess they have all been hiding too. Funny but EVERYONE of them has heard of Clarence Lee and George Aldrich.
Artisan,
Who said anything about being picked on". You said that because YOU were an old fart you "cracked on people who don't do things the old fashioned way". Well, I'M an old fart and I have NO problems with modern things and modern ways so don't lump all "old farts" together.
06-28-2006, 09:14 PM
#20
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RE: OS or Magnum Carb.......
Tirade? I think you better check the definition of the word tirade in the dictionary. I mentioned it because Artisan said he liked the old fashioned way of doing things and BUILDING an airplane rather than BUYING one already built is the old fashioned way. I bet he has owned an ARF.
06-29-2006, 11:28 AM
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RE: OS or Magnum Carb.......
wow, i thought we were talking about carbs, oh well. I bought the Magnum 108 carb. Hope it fits..................
06-29-2006, 02:35 PM
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RE: OS or Magnum Carb.......
ORIGINAL: gapple12
wow, i thought we were talking about carbs, oh well. I bought the Magnum 108 carb. Hope it fits..................
wow, i thought we were talking about carbs, oh well. I bought the Magnum 108 carb. Hope it fits..................
Thanks,
Ernie
06-29-2006, 04:17 PM
#24
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RE: OS or Magnum Carb.......
ORIGINAL: loughbd
Tirade? I think you better check the definition of the word tirade in the dictionary. I mentioned it because Artisan said he liked the old fashioned way of doing things and BUILDING an airplane rather than BUYING one already built is the old fashioned way. I bet he has owned an ARF.
Tirade? I think you better check the definition of the word tirade in the dictionary. I mentioned it because Artisan said he liked the old fashioned way of doing things and BUILDING an airplane rather than BUYING one already built is the old fashioned way. I bet he has owned an ARF.
-------------
Alas, the truth is revealed. Yes, I have a bunch of ARFs. <G>
06-29-2006, 04:23 PM
#25
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RE: OS or Magnum Carb.......
ORIGINAL: gapple12
wow, i thought we were talking about carbs, oh well. I bought the Magnum 108 carb. Hope it fits..................
wow, i thought we were talking about carbs, oh well. I bought the Magnum 108 carb. Hope it fits..................
------------------
A new Perry carb that will fit the G90 (model #4500) costs $24.95 plus shipping when purchased on the world famous internet auction site.
That is what I'm going to buy if the need arises and I don't feel like messing with the Moto Tool on my stock carb.
The ASP/Magnum 1.08 carb is just as large, or larger, than the stock carb. I don't see much of a gain by going with that carb.
The Perry is available in two sizes with a .540" neck shank. The "00" carb (4500) has the standard size throat. The "01" carb (4501) has the larger throat. I'm going for the "00" to get back some air velocity/better throttling. I'll never miss that 100 rpm that the larger carb might provide.