How about 2-speed on Rampage

[DemonRC]

Oh my. Have I got something for you guys within the next few months. A gauranteed jaw dropper


Anyways, I examined and reproduced the Skunkworks design in AutoCAD to use as reference for future projects. Ya the design looks bulletproof. It's a definate improvement over the FG design but for some reason the one-way bearing detonates within a few minutes of running. I've seen it happen on 3 guys I know all within the same day of them getting the tranny. Now another buddy of mine got a hold of another 2 speed ( I forget the manufacturer but it's somebody from the UK) and it's been holding up well considering it has duel one-ways. I think if you took the overall Skunkwork design and paired it with the duel one-ways you would have a bullet-proof design.

 

[RampageHopUps]

The BSW 2 speed only needs a non-cheapo CHinese bearing. The guys running Torrington one way bearings are not having problmes.

 

[Martin]

My plan is to use two 10mm ID one way bearing like FG, they are smaller than the BSW and BRCP owb but will hold fine for several tank.


don't forget that the spur gear design on an hpi Baja multiplies a lot of torque from the engine to the owb ( if 17/57 pinion spur = 3.35:1) and the higher you will see on a Rampage would be around 1.4:1, a lot more easy on the bearing.

 

[DemonRC]

The BSW 2 speed only needs a non-cheapo CHinese bearing. The guys running Torrington one way bearings are not having problmes.

Ya they exploded higher quality bearings too. I can't say they were "Torrington" owb's since I don't visit HBF anymore but it was some bearing manufacturer recommended on HBF to fix the problem.

 

[Toyonka]

have you guys seen this 2 speed tranny for the HPI? may work on the rampage...

 

[DemonRC]

Ya, that's one of few chinese 2 speeds that are coming out. The problem I've had with developing 2 speed using gears is that, first, all those gears weight too dam much. 2nd it sticks out way to far. The very first time you get T-boned you will most likely bend the layshaft and screw up the gear mesh. Once you bend a shaft slightly you have exponentially shortened the lifespan of the bearing and then you can kiss those gears goodbye. Been there done that


Gear driven 2 speeds are about to be extinct by springtime if everything I've been working on for the past year keeps going as planned.


BTW, thanks for deleting that link Rob. Dam Chinese pirating is bad business.

 

[Toyonka]

ohh, thanks for pionting that out. I didn't know.


btw: isn't everything now a days made overseas, with the exception of 5% of the products out there. hell, even the rampage is manufactured in china.

 

[RampageHopUps]

I deleted it for a stolen design, not for where its was made.

 

[DemonRC]

Ya I got nothing against Chinese manufacturing. It's the "Chinese pirating" that get's to me. Reverse engineering product and then selling it for a fraction of the cost is just plain wrong.

 

[pipeous]

yes, I agree. I was talking to Dino at Jet Pro today and he found someone making copies of his pipes, branding them as jet pros and selling them. I really hate that myself. and to try and pawn it off as an actual jet pro.


worst part for some of this stuff is it looks good but you find out later it's just crap materials and you wasted money and end up buying the real stuff...


anyway. dirt and one way bearings are a bad marriage. and the way the fg 2 speed shifts really needs an update. the part that swivels out and catches the pin is another bad design. if the revs hit shift just after the pin, there is almost a full revolution before engagement. this hits the pin hard and wears them fast. a better idea would be swivels at 180 degrees to lighten the impact a bit. I replaced those pins with fg lower shock screws many times until the swivel wore out and would never shift again. I'm back to single speed. less chance to have something wear or break to end my day. KISS principle. that $250 buys other things I need like a set of tires hehe

 

[DemonRC]

Ya I didn't like my FG 2 speed either. Bent pins were a pain. Here's an improvement. I figured the backing behind the pins out years ago and drew it in ACAD way before BSW released their 2 speed so don't slam me for the backing behind the pins. It was just common sense for anybody that has ever run the FG 2 speed. Don't ask what's going on that carrier cause I'd have to kill you if I told you.



/monthly_2010_10/carrier.jpg.2c3c070ec8e19f9577d483ebbf15b482.jpg

 

[Martin]

Ya I didn't like my FG 2 speed either. Bent pins were a pain. Here's an improvement. I figured the backing behind the pins out years ago and drew it in ACAD way before BSW released their 2 speed so don't slam me for the backing behind the pins. It was just common sense for anybody that has ever run the FG 2 speed. Don't ask what's going on that carrier cause I'd have to kill you if I told you.

A piece of hard rubber to dampen the shock........ ?


I also used an FG two speed for a long time, I have to admit that this is never perfect, sometime it does not shift, sometime get stuck in 2nd....... and what I hate the most is that undesirable shifting when the buggy hit a bump.


Now a problem for the Redcat / MCD, to make a two speed I must install 37T on the clutch bell and 23T on the middle shaft, ( I don't talk about 1st and 2nd gear ratio), and with that 37/23 ratio when the engine rev for ex: an average of 17000 + rpm, the middle shaft turn 1.6 X faster, close to 28000rpm, I first tested this configuration last week and it took 30 second for the middle shaft bearing to desintegrate and melt the gear plate at the same time, this was with the stock Redcat shielded bearing, I do not tested it with different bearing, I will have to check for a better one, but they are hard to find in that size.

 

[Toyonka]

I see your guys' piont, I'm not for stealing designs and rebranding them either ....but unfortuneatly, it is what brings down the cost of products and makes them more accessably ie cheaper to the average joe.


I'm not trying to make this into a pissing contest, please. All I want is to make my rampage go faster by means of a second gear . And if someone here has a design, then please start manufacturing it so that the rest of us can just simply go faster

 

[DemonRC]

Anybody wanna see a video of one actually working on a heavy ass MCD Evo 4? I could slap a spare prototype in my XT in about 5 minutes but I wouldn't have any more friends at the track after I ran it.

 

[bbuzzard]

Yes, please!!!

 

[rob64n]

bring on the video, we like videos

 

[DemonRC]

Vid is up in the General section.