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is the o.s. max .21 any good
- Thread starter lmaxx8
- Start date
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scottm
Hardcore RCTalk User
Do you have the 21 RG? Those are great engines. They have good low to mid torque, and will last forever with good tuning and maintenance. The weak points are the one-way bearing in the pull starter (expensive) and the connecting rods are fragile (do not hold it wide open with the wheels off the ground).
scott do you know of anyone making replacement conrods for an RG...actually do ya know if any other ones fit?.....I polished the crank and beveled the intake on the crank and polished the intake and exhasy ports in the case....and just polished the sleeve ports.......it freakin screams....big difference...but now I have a really nice mill w/ a weak conrod......any suggestions....
vbgagnon
RCTalk VIP
I'm thinking of picking one of these RG's up. Plaid I know you race with it, but how is the power? I've read that its got great low end but the top isn't that great. Would a 086 pipe help in this dept? Also does it or does it not come with a special header? Is it a header that ties to a 1 piece pipe or do I need to use a silicone cuppler?
scottm
Hardcore RCTalk User
Plaid, there really isn't a problem if you don't overrev the engine. Just be careful to keep it on the rich side, especially for high speed running. I have broken 2 myself, but both times were bonehead mistakes.
vb, the 21 rg does require a speacial header, which RC Solutions just happens to make. It was designed to fit a pipe inside an rcs roll cage, but people use them for all kinds of cars.
https://securehost59.hrwebservices.net/~rcsolu/products/product_details.php?id=2&CID=TRAXXAS
vb, the 21 rg does require a speacial header, which RC Solutions just happens to make. It was designed to fit a pipe inside an rcs roll cage, but people use them for all kinds of cars.
https://securehost59.hrwebservices.net/~rcsolu/products/product_details.php?id=2&CID=TRAXXAS
wow now where was that when I was axin bout em.....that looks too cool.....how would I connect that to an 063 pipe????
VB I use an 063 and just raise the CB when I run at the track w/ long straights...it kills bottom end but I can get it to hang w/ alot of the big dogs running.....my skills fall short when it's hole shot type battles....I always leave mine a little fat onthe bottom for the reasons scottm said...the conrod.....they're real easy to tune (2 needle) and they hold it well.....I like em cause they're inexpensive and when they go it's a good mill to strip and sell parts for or try modding them...I just did my first mod and ran it last night....polished the crank and beveled the fuel intake on the crank....polished the intake and exhaust ports in the case and polished and rounded a conrod but I didn't put that one in yet....waiting to let the local master modder look it over first....it made a huge difference on mine......also I do th estand break in on them now....just finished gal 3 last nite in that mill and still feels like it has awsome compression....lil hard to turn even.........I have another RG crank I'm going to try and turbo cut.... but I need a timing wheel first....I'd rather try the cheapos and ruin them before I try an expensive mill....but I'm sure I will get it right
the mill comes w/ a coupler backplate for the standard type headers but that RCsolutions one looks beefy and would bolt right to the crank case from the looks of it......I can see using that on a truggy or MT but it might be too rigid for some of the cartwheels my buggy does....intentionally of course
VB I use an 063 and just raise the CB when I run at the track w/ long straights...it kills bottom end but I can get it to hang w/ alot of the big dogs running.....my skills fall short when it's hole shot type battles....I always leave mine a little fat onthe bottom for the reasons scottm said...the conrod.....they're real easy to tune (2 needle) and they hold it well.....I like em cause they're inexpensive and when they go it's a good mill to strip and sell parts for or try modding them...I just did my first mod and ran it last night....polished the crank and beveled the fuel intake on the crank....polished the intake and exhaust ports in the case and polished and rounded a conrod but I didn't put that one in yet....waiting to let the local master modder look it over first....it made a huge difference on mine......also I do th estand break in on them now....just finished gal 3 last nite in that mill and still feels like it has awsome compression....lil hard to turn even.........I have another RG crank I'm going to try and turbo cut.... but I need a timing wheel first....I'd rather try the cheapos and ruin them before I try an expensive mill....but I'm sure I will get it right
vbgagnon said:
the mill comes w/ a coupler backplate for the standard type headers but that RCsolutions one looks beefy and would bolt right to the crank case from the looks of it......I can see using that on a truggy or MT but it might be too rigid for some of the cartwheels my buggy does....intentionally of course
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vbgagnon
RCTalk VIP
I think I'm going to do it! You can't beat an OS mill and for $100 def nothing wrong with that!
Is the OS 21 Maxx the same as the OS 21 RG?
I run the RG in both my savage and my buggy. It really likes the open pipe like the HPI ribbed (buggy) and the HPI polished tuned pipe (savage). I was running a XTM t-maxx 21 conversion pipe and when I switched, it was like night and day through the whole RPM range. Better low end and it screams to the top a lot faster. Also sounds like I'm getting more RPMS out of them, especially with the HPI polished pipe.
If you treat a RG right, you can get many gallons out of them. I just had the one in my buggy pinched about a gallon ago and it was on 9 gallons then. It just started flaming out on me for no reason. Got it pinched, dealt with tight pinch for about 1/2-3/4 gallon and now it's starting to open up and run good again.
I run the RG in both my savage and my buggy. It really likes the open pipe like the HPI ribbed (buggy) and the HPI polished tuned pipe (savage). I was running a XTM t-maxx 21 conversion pipe and when I switched, it was like night and day through the whole RPM range. Better low end and it screams to the top a lot faster. Also sounds like I'm getting more RPMS out of them, especially with the HPI polished pipe.
If you treat a RG right, you can get many gallons out of them. I just had the one in my buggy pinched about a gallon ago and it was on 9 gallons then. It just started flaming out on me for no reason. Got it pinched, dealt with tight pinch for about 1/2-3/4 gallon and now it's starting to open up and run good again.
scottm
Hardcore RCTalk User
Olds, OS used to be called OS Max, now its just os engines. They have several 21 size engines, here is a link to the 21 rg series.
http://www.osengines.com/engines/osmg2055.html
http://www.osengines.com/engines/osmg2055.html
funny how they still have the RZ listed.....
Olds you should try the 063 pipe if you can....I ran mine on the HPI pipe at first...it's good but the 063 gives some punch off the line that makes the ribbed pipe seem like a dog....
VB you won't be dissapointed for the cash they cost.....it's no WS72 or 421 but it definately scoots along fast enough....I think it's a great practice mill......I haven't even put my VZ-b back in since I re-pinched it and replaced the rear main......I'm having a blast getting this thing to scream for me.........
Olds you should try the 063 pipe if you can....I ran mine on the HPI pipe at first...it's good but the 063 gives some punch off the line that makes the ribbed pipe seem like a dog....
VB you won't be dissapointed for the cash they cost.....it's no WS72 or 421 but it definately scoots along fast enough....I think it's a great practice mill......I haven't even put my VZ-b back in since I re-pinched it and replaced the rear main......I'm having a blast getting this thing to scream for me.........
