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Engine basics => Four strokes only => Topic started by: Bob Reeves on January 26, 2012, 07:37:25 AM

Title: Why not to run castor in a 4 stroke
Post by: Bob Reeves on January 26, 2012, 07:37:25 AM
In one of my previous posts I mentioned changing the cam in an very experienced Saito 56. After changing the cam I put the engine on my test stand and the best it would do was just over 5 grand. I double checked my timing set up and came to the conclusion that (sad to say) the engine has issues. Shined a light in the exhaust port and this is what I saw..

Engine on the left is the 56 I ran in a Score for a season and a half on YS 20-20 the one on the right is the poor 56 that was mistreated.
Title: Re: Why not to run castor in a 4 stroke
Post by: Lauri Malila on January 26, 2012, 01:27:35 PM

 Hi.

 Just an opinion, but..
 I know very succesfull sportsmen who use castor oil in their 4-strokes (mostly Saito .56). For example Beringers and Luc Dessaucy. I pretty sure they use at least 50% of castor in the oil mix.
 And what I have observed, these engines run the best compared to the other 4-strokes seen in competitions over here.
 But what I've learned from Luc especially, you must prepare yourself to dismantle & clean the engine more often, and these guys also rework their engines in order to minimize the friction between the moving parts (mostly re-lapping and polishing of functional surfaces).
 I've seen many people go the other way with all synthetic with varying results, but these engines seem to be missing something in the harmony.

 Lauri   
Title: Re: Why not to run castor in a 4 stroke
Post by: Dennis Adamisin on January 26, 2012, 05:22:35 PM
So, Dr Bob, can the patient be saved?  De gummed, maybe a new ring & hone job? 
Title: Re: Why not to run castor in a 4 stroke
Post by: Mike Callas on January 26, 2012, 10:59:07 PM
Bob,
I think I have a contender for the next contest's motor toss!

Mike
Title: Re: Why not to run castor in a 4 stroke
Post by: Brett Buck on January 27, 2012, 12:08:15 AM
Bob,
I think I have a contender for the next contest's motor toss!

   I want 50 geezer points to throw that baby!

    Brett
Title: Re: Why not to run castor in a 4 stroke
Post by: Bob Reeves on January 27, 2012, 08:07:33 AM
So, Dr Bob, can the patient be saved?  De gummed, maybe a new ring & hone job? 

General consensus is it isn't worth the parts it would take to make it whole again. A good used Saito 56 can be found for 100 to 150 and it would take at least $100.00 in parts to fix this one and that is assuming the cylinder doesn't need replacing. Mike is going to buy a new 62 and put the reverse cam in it.

Wished I had drug my feet a little longer to modify the RC carb that was on this engine, looks like he is going to buy the CL version because it is less money. The RC carb would have been nice to have for break in and I could do my mod to the CL intake. Come to think of it, I probably have an unmolested RC carb. Hummmmmmm
Title: Re: Why not to run castor in a 4 stroke
Post by: Bob Reeves on January 27, 2012, 08:22:22 AM
Hi.

 Just an opinion, but..
 I know very succesfull sportsmen who use castor oil in their 4-strokes (mostly Saito .56). For example Beringers and Luc Dessaucy. I pretty sure they use at least 50% of castor in the oil mix.
 And what I have observed, these engines run the best compared to the other 4-strokes seen in competitions over here.
 But what I've learned from Luc especially, you must prepare yourself to dismantle & clean the engine more often, and these guys also rework their engines in order to minimize the friction between the moving parts (mostly re-lapping and polishing of functional surfaces).
 I've seen many people go the other way with all synthetic with varying results, but these engines seem to be missing something in the harmony.

 Lauri   

Everyone needs to do what works for them and the people in this hobby have always found more than one way to get where they need to be. I'm sure if what the Beringers are doing is followed EXACTLY one would get the same results. I also know from feedback if my setup and suggestions are followed EXACTLY it also works. Sad part is we were a little late getting to the party, the 4 stroke peak has came and gone in the US without many being able to experience what a 4 stroke is really capable of doing.
Title: Re: Why not to run castor in a 4 stroke
Post by: proparc on January 27, 2012, 05:54:36 PM
Sad part is we were a little late getting to the party, the 4 stroke peak has came and gone in the US without many being able to experience what a 4 stroke is really capable of doing.

Not in RC it ain't. But, 4 strokes in stunt really require some local "guru" who knows what he is doing and can set the other cats right. For me, my RC experience really made 4 strokes a no brainer in stunt. I personally see them as more fun than a barrel of monkeys. I, like most Saito owners, I simply want more of them.

As a side note Bob, the rumour going around RC is that, the Saito 62 may be the best Saito of all time, interesting.
Title: Re: Why not to run castor in a 4 stroke
Post by: Bob Reeves on January 30, 2012, 08:42:22 AM
<snip>
As a side note Bob, the rumour going around RC is that, the Saito 62 made be the best Saito of all time, interesting.

That and the 40.. I wouldn't hesitate to stick a Saito 40 on anything that an LA 46 is flying.