new 70cc 18hp engine

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Renbar and hyper nailed on both points. Thanks. The days I shot those vids I was by myself, my buddy was laid up from a operation. The vids were taken to show the raw power that most of us like to see. The motor is currently not available as of yet. But, if you email the guys at ultimate RC in the UK, they will be selling it and there is a waiting list they can place you on.

http://www.ultimate-rc.net/
 
my 2 cents is that the motor would be great to have. since the closes track to me for 1/5 scales is about 3.5 hours away and since i work 6 days a week i really don't have the time to drive all that way to race. so bashing is all i have and since that motor is made for bashing .......... bring it on.
 
where can you even find these?not that i would actually be in the market for 1 as im sure it is over 1 grand at least,but i would at least like to drool over a sellers ad for it
 
This engine looks like a killer, I am impressed on how it pushes the big Losi 5ive effortlessly.

I'm definitely gonna try one out.​

 
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I've seen few 50cc BZMs and I also have one myself in a sandrail. This RCMAX70 is interesting but I agree what people say about it on at least couple of occasions.

First is that it's useless on a 2WD, better suited for heavy 4WD.

Secondly the power is not so impressive actually I would think a ported BZM has more. Sure this might have more bottom torque but I have the impression the BZM has more on top. I don't have an RCMAX to compare side by side so this is just quesstimatin'. My 50cc BZM has a Scott Finlay -ported cylinder and to me the performance is very impressive with the pipe I have. I also have BZMs own 85mm adjustable clutch to handle the power and it has proven to be bomb-proof.

Third (which has not been said here) is when you put an engine into these big toys and can't use a body on them anymore then it's not for me. To me those kraken-equivalent cages or whatever are just so goddamn ugly.
The only sandrail that I have (equipped with the ported BZM) is the one-off that was built by Brice Arnold of BSW and is the only sandrail that ever really attracted me visually in rc-size.

Fourth, related to Third somewhat is the cooling which is very problematic. Especially with pipes running in front of the engine like this engine and also commercial versions of the BZM. My BZM in my sandrail has the pipe running behind the engine completely because the sandrail has room for that. This pipe is a modified version of this particular engines best racing model, not my own design in this case. My 100cc twin has the pipes also running behind the engine, has a body and has also overheating issues if you run it on a hot day if you don't keep the speed up. During winter it's a blast but currently I am making the pinion and spur stronger as it ripped the steel teeth off on both those parts.

Last point, I see the pipe is a compromise to say the least. If you would want to unleash all the potential of this engine the pipe would need to be so big in many dimensions that the only question would be "Where's the car?" underneath that pipe. So you start to run out of room with these engines and with 2-stroke engines the pipe is the most important thing that should have the least amount of compromises built in.
 
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JariV said:
Secondly the power is not so impressive actually I would think a ported BZM has more. Sure this might have more bottom torque but I have the impression the BZM has more on top. I don't have an RCMAX to compare side by side so this is just quesstimatin'.
Click to expand...

From looking at the videos and speaking with actual owners its apparent that the RC Max makes excellent power.

Just looking at the above video and seeing the heavy 4WD Losi 5ive-T being pushed to those speeds and acceleration is impressive.
 
id say the rcmax has more power and torque then the bzm 50 super, just don't rev as high but being able to pull 30/44 gears offroad while roostering and strong power through out to 80mph means its not that bad.they rev to 17k. they have 3hp over the 50 super and about 3 lbft.
the 70 is no problem in a baja as long as its set up right.videos of people showing off its torque makes it look too much.
one important thing when spending this sort of cash on an engine is customer service, reliability.id say rcmax trumps the bzm in both departments.
ive had scottys porting on a 30.5, a great engine cant fault his work.the rc 40 also looks a great engine.id like one.

the video above of the losi is effortless power, the owner has bigger gears coming, even using these gears he claims he hasnt lost 1 rpm from the lower gears.
if you search both engines for problems, youll see the rcmax is probably the most reliable.
I wanted a 50 super but after months of researching, there was only one choice for me but I guess everyones different.

also the 70 isnt at its limit, ive been speakin to chris and he offered more porting if wanted, power is enough for now but abit more rpms might be on the cards, we'll see.
 
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looking good pal.hope you got some BIG gears to go with it.
just for your information, I had a problem with my carb (cleaned it out, didnt hook the diaphram back up , user fault) I emailed chris and within 2 minutes he was on the phone and problem solved.
like I say when you spend so much you need the backing of the builder...no waiting weeks or months for parts... upto now there have been no issues with any rcmax according to c.d except for one that got driven into the sea, after a piston , ring change that ran like a champ again.chris' s has done crazy amount of tanks on his 70 and still running same ring etc..
 
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I got to agree, the killswitch and good brakes are a must, although it was tempting i didnt run without one, I thought id be ok using one of my spares but a boat killswitch is used on the rcmax.
I use the superbee boat killswitch, works great.
 
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