Are these engines owned by the same company or distributor I get their made at the same factory but so are a lot of engines example LM. The Argus engines were a great option for people sold more then a few all great comments maybe theirs stretegy behind this increase doesn't make sense why would you increase without explainined while showing the value. Who's representing the product in the US now ??

I was told by someone at Argus in an e-mail that low price= low quality, they raised the price to somehow make it seem like a higher quality motor.

No one that I know of is importing or supporting Argus. Most Alpha parts will work. I sold a bunch of Argus, most of them because it was basically an Alpha at a cheaper price. Now that they are not cheaper there is no reason to sell them when Alpha is available and supported. (And the Lutz engines look awesome:))

Rex

Argus A5 shimming + pitting
 

Hoping for some help from the most active Argus forum/thread, which prompted me to buy the A5 recently. Came with a Hong Nor 2080 pipe.

So I had my LHS run it in for me with the extra shim. He only put about 3-5 tanks through it and I put the rest of a gallon of 25% Byrons. About 3/4 through the gallon, it still wasn't developing much power so I took the extra shim out. Got a noticeable jump in power, but still not what I would call lively.

Just checked and the shim in place is .20mm. I can't seem to find the other shim, which I presume would have been the .10mm. Whilst checking the shim, I noticed some light pitting on the piston and the filament is a bit white. Is this because I'm running lean?

Temps are around 260 deg F or 125-130 deg C.
Glow plug is T3 (alpha?) that came with the engine, but I have 97T O'Donnells I can use instead.
I'm in UK, so ambient temp isn't very high.
I have 30% Ammo fuel I would like to use, but can stick to 25% Byrons.

My main question, is what size shim are people using? I've read most of this thread and searched for references to shims. Someone reported they were running 30% on .40mm shim during break in and .30mm after. Most other references to shim simply state whether they were running with or without the extra shim etc, but don't mention what size shim is left in place. Should it be .20mm on 25%?

I've also found some information about pitting being due to running lean or incorrect shimming, but again, the information I've found doesn't mention whether pitting is caused being over or under shimmed.

Would really appreciate any help, John

P.S. I'm not allowed to post links yet, but will add pics if required once I've made a few more posts.

Can't help you I'm afraid. My A52 is running fantastically.. Shimming is whatever it came with. I would absolutely buy another A52 with zero hesitation.

I bought an A852 and compared it to the A52 and to be honest the A852 has more power. The same exhaust and buggy was used in both engines. Like it was mentioned before some parts are interchangeable, but to be honest I see no reason now to buy another Argus since my experience has been slightly better with the Alpha, not to mention the customer service is outstanding in the USA (Argus has no representation in the USA now).

I would love an A852 - but they cost a fair bit more than the Argus did.. - a good %20 more now(%30-40 more when they first came out, when I bought my Argus..) And in my case I got my Argus extra cheap from a shop which was auctioning them off.. I keep an eye out for deals for the Alphas, but they don't come up nearly as often as the Argus deals did..

What's the going rate for a new A852 anyway?

The Alpha A852 is $229.99 map price.
As for shimming witht he Argus it should be the same as the Alpha's, one thicker .2mm shim and a .1mm. I personally think you can get by running 30% with just the .2 shim if you ran a bit cooler plug.

Rex

Thanks for the reply Rex,

I found the extra shim and it was indeed 0.10mm. Adjusted the tune a bit, but also noticed my gearing was way off. Engine came to life with the right gearing and better tune.

So I'm still running on the original Alpha T3 plug with Byrons 25%, but have O'Donnells 97T plugs and 30% Ammo fuel standing by. Would you say I could run the 30% Ammo with the 0.20mm shim and 97T plug? It's a medium plug - is that cool enough or should I put the 0.10mm shim in?

Weather in UK is around 26°C / 79°F at the moment. Running buggy on dirt.

Cheers, John

I would run the .2 and a.1 for a total of .3 with the 30%. You could try just the .2 shim but if it blows a plug or is hard to tune add the .1.
The extra shim that comes with the motor in the little plastic wrapper is a .2, not sure if that was the one you found or one that was taken out.

Rex

Thanks Rex, I think the .2 shim was what came fitted to the engine and the extra/break in shim was the .1 shim. If anyone could confirm this I would be grateful.

I'll try the 30% with both shims in and see how I get on.

Cheers, John

A5 factory shimming is .3mm total, (1x.2 1x.1 shim) The optional extra run in shim is .2mm

Thanks mate, I did find another .2mm shim, but I thought that was from another engine because it was a bit discoloured and looked older. So if the engine came with .2mm + .1mm and I added the extra extra .2mm for break in, I must have taken 2 shims out by mistake (a .2mm and a .1mm) leaving just .2mm in the engine.

Would this slight increase in compression contribute to the slight pitting on the piston? TBH, it hasn't had much fuel through it with just the .2mm shim in and it could have also been down to a poor tune.

I guess I should also change the conrod too, just in case.

So what shims should I have in for 30% fuel? .40mm total? Information has been hard to find but it seems from the quote below that the A52 also comes shimmed at .3mm although it comes with a slightly thinner extra/break in shim.

For 30% use the standard .3mm shims. I run 25% with .2 shim. 97T or P4 good plug choice, those T3 were pretty erratic, unsure about the new batch. I would change the rod shortly just for peace of mind, unsure about pitting of piston, if it is very minor then maybe it was under shimmed and too lean. If it is quite bad i would be stripping the motor, check the bearings etc.

So is the B52 even being sold anywhere in the world? Videos?

Thanks again, the pitting has happened whilst running 25% with the .2mm shim. Once I've got some more posts, I'll add a pic. Although it's not heavy pitting, it's happened in about 1/2 gallon.

I'll change to the 97T plug, shim to .3mm and see how it goes on 30%. Will polish the top of the piston to keep an eye on any further pitting.