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Old Nov 09, 2012, 01:31 AM
If u aint 1st your last
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Sydney, Australia
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Originally Posted by chktm View Post
Wow TJ that sounds awesome. To me up in Qld it says $40 for the Snail mail and $60 ish for priority paid. I guess you'll have yours up and running soon . Be careful using the battery as the connectors squeeze the speedo plugs too tight and then when used with the correct ec3 plugs can cut out. Glad you and your mate enjoyed the bike. You might want to make up a wheelie bar for them and shoe goo the rear guard. Demoed my bike today and could have sold 2 in 5 mins.
Ok mate, im working on wheelie bars now, i hope i get mine as quick as you got yours i am keen now after having a go of the mm.
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Old Nov 09, 2012, 05:34 AM
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Originally Posted by Throttlejunkie View Post
Ok mate, im working on wheelie bars now, i hope i get mine as quick as you got yours i am keen now after having a go of the mm.
You'll probably get yours quicker than me as mine would have to come in through Sydney I think. They are really easy to use as you found out. Yours might be more of a monster lol.
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Old Nov 09, 2012, 10:05 AM
build, fly, crash...repeat
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United States, WA, Redmond
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Originally Posted by Chris Nicastro View Post
No the hardened rear axle was discontinued because there was no need for it. the stock rear axle is the only one offered, ever. The rest of the parts will be in production for now and as long as well sell the VMX mechanical gyro. The parts will be supported for about a year or more after they are officially discontinued which is our standard practice.
If you have any problems ordering from our UK Dealers let us know and we can help you out.
Note - be very, very careful when installing the new included (egyro) rear axle. The one that shipped with my egyro upgrade had the nyloc nut cross threaded and broke when trying to get remove the nut, and the replacement shaft I ordered and just received broke as well when installing on the bike.
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Old Nov 09, 2012, 12:40 PM
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hummm... got an issue maybe others could identify ~ i've ran many many packs with egyro 4800, stock pinion, no problem.

replaced with 13t and now bike has a dead spot @ 1/3 throttle, especially if I punch it no response from motor unless I gradually get to speed. lipos arent old. Do I need better esc? 4800 too much?

prolly just switch back to stock pinion to fix - thanks for helping
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Old Nov 09, 2012, 04:03 PM
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Originally Posted by elvill View Post
hummm... got an issue maybe others could identify ~ i've ran many many packs with egyro 4800, stock pinion, no problem.

replaced with 13t and now bike has a dead spot @ 1/3 throttle, especially if I punch it no response from motor unless I gradually get to speed. lipos arent old. Do I need better esc? 4800 too much?

prolly just switch back to stock pinion to fix - thanks for helping
Yea speedo can't cope with the load I think with the 4800 kv motor, mine does it sometimes but not often. I'm ordering a 100 amp speedo anyway as I want it for the Tenshock motor. Maybe try an 11 or 12, less load. Do you drive on grass or bitumen? This will make the flat spot more apparent more often as has more load.
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Old Nov 09, 2012, 04:11 PM
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Originally Posted by marksp View Post
Note - be very, very careful when installing the new included (egyro) rear axle. The one that shipped with my egyro upgrade had the nyloc nut cross threaded and broke when trying to get remove the nut, and the replacement shaft I ordered and just received broke as well when installing on the bike.
Can't see what you are doing to brake the shafts, I install two washers each side before the nuts this lets me tighten the nuts without the threads bottoming, this could be your problem. Maybe stop tightening when the nuts run out of thread. these don't have to be cranked up super tight. I've broke one shaft so far on a massive flat landing nose high obviously with no suspension.
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Old Nov 09, 2012, 05:26 PM
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Waterford, Michigan
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Originally Posted by chktm View Post
Can't see what you are doing to brake the shafts, I install two washers each side before the nuts this lets me tighten the nuts without the threads bottoming, this could be your problem. Maybe stop tightening when the nuts run out of thread. these don't have to be cranked up super tight. I've broke one shaft so far on a massive flat landing nose high obviously with no suspension.
I'm having an issue with the e-gyro axle also, but different than either of what you guys are talking about. My axle became bent on my VMX bike from running on my basement track jumps! The bike never has gone over 10 or 12 mph, lol. I never knew I had an issue until my gyro quit working and I was trying to remove the wheel to check the wiring and the axle wouldn't slip out of the hub from one direction. Both ends were bent but one side was bad enough not to slip out.
Sounds to me like they are having heat treating irregularities with the the axles either being too soft like mine or too hard like you guys are seeing.
I called Atomic with my gyro issues and (I think I talked to Mike?) he told me they had some stronger axles there now and he would send me out the replacement and a new stator and ESC for the gyro. The gyro quit because two of the 3 wires exiting the wheel had damaged insulation and shorted into the inner race of the bearing and smoked the esc! Apparently the damage was done at the factory when the wheel was assembled. Hopefully mine will be the only failure of the bunch! Those stiff little wires have to make such a tight 90* bend to mount to the fake brake caliper I can see that if you weren't careful the wires would be bent too early and contact the edge of the bearing I.D. . I will look at grinding some relief in the back side of the fake brake caliper for sure.... OH, BY THE WAY THE TECH GUYS AT ATOMIK ARE GREAT!!
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Old Nov 09, 2012, 05:41 PM
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Originally Posted by TopDave View Post
I'm having an issue with the e-gyro axle also, but different than either of what you guys are talking about. My axle became bent on my VMX bike from running on my basement track jumps! The bike never has gone over 10 or 12 mph, lol. I never knew I had an issue until my gyro quit working and I was trying to remove the wheel to check the wiring and the axle wouldn't slip out of the hub from one direction. Both ends were bent but one side was bad enough not to slip out.
Sounds to me like they are having heat treating irregularities with the the axles either being too soft like mine or too hard like you guys are seeing.
I called Atomic with my gyro issues and (I think I talked to Mike?) he told me they had some stronger axles there now and he would send me out the replacement and a new stator and ESC for the gyro. The gyro quit because two of the 3 wires exiting the wheel had damaged insulation and shorted into the inner race of the bearing and smoked the esc! Apparently the damage was done at the factory when the wheel was assembled. Hopefully mine will be the only failure of the bunch! Those stiff little wires have to make such a tight 90* bend to mount to the fake brake caliper I can see that if you weren't careful the wires would be bent too early and contact the edge of the bearing I.D. . I will look at grinding some relief in the back side of the fake brake caliper for sure.... OH, BY THE WAY THE TECH GUYS AT ATOMIK ARE GREAT!!
Could be the heat treatment yes Dave. I bent one much like you within 5 mins without crashing. A rock got jammed in the chain and this bent the axle. I replaced and have since had many rocks jammed and never bent another. Also been doing those big jumps and backflips and crashing. Good to hear that stronger ones are available. Atomiks service is great all right.
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Old Nov 09, 2012, 07:54 PM
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What is the best wheelie bar out and where can I get it?
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Old Nov 10, 2012, 03:03 AM
build, fly, crash...repeat
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United States, WA, Redmond
Joined Apr 2011
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Originally Posted by chktm View Post
Can't see what you are doing to brake the shafts, I install two washers each side before the nuts this lets me tighten the nuts without the threads bottoming, this could be your problem. Maybe stop tightening when the nuts run out of thread. these don't have to be cranked up super tight. I've broke one shaft so far on a massive flat landing nose high obviously with no suspension.
Yeah, I'll add a couple of washers to shim it up, thx.

+1 on Atomik support! Great service!
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Old Nov 10, 2012, 08:05 AM
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Australia, SA, Adelaide
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vmx wheelie bar

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Originally Posted by Rellik View Post
What is the best wheelie bar out and where can I get it?
no one makes one as such as far as i know relik ,apart from the stocky,best bet make one up,there has been a few posts with ideas best one i saw was an alloy support cross brace type,with a small wheel fitted................
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Old Nov 10, 2012, 11:53 AM
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Originally Posted by Rellik View Post
What is the best wheelie bar out and where can I get it?
Let us consider what a wheelie bars' function is.

Its main aim is to protect the rear mudguard (fender) from damage when you have the bike flip onto its back.

As a side benefit, you can go one of two ways.

The 'Wheeled' wheelie bar:
This allows you to get up into a wheelie and then allow that wheelie to continue by virtue of the rear wheelie bar wheel stopping any drag and keeping the centre of gravity between the rear driven wheel and the wheelie bar wheel. This essentially makes the bike a very high centre of gravity short wheelbased version of itself as two wheels are on the ground. Only with this version, you can't turn as both wheels are in a fixed plane. On tarmac or other smooth flat surfaces, you can keep the wheelie going for as long as you have room or until you hit the brakes.

Off road, this facility to keep the front wheel high in the air can lead to problems, especially with an M-Gyro. As the gyro slows, the bike is more susceptible to bumps, which combined with the artificially high centre of gravity, makes it very unstable and likely to pitch over to its side. Further, as the gyro slows, it can tie itself in knots as a phenomenon known as the Conservation of Angular Momentum comes into play. This makes the bike wriggle and spin with no control whatsoever. Luck then tends to come into play as to how the bike finally comes back into control, usually by laying down on it's scratchbars, and more often than not, facing the wrong way to the intended direction of travel.

An E Gyro will resist the angular momentum force but it will still not be able to counteract the bumps found off road when the bike is running a high centre of gravity, therefore, the wheelie may continue longer versus an M-Gyro, but you wont beat the track. The bumps will still throw you off line eventually.

You can make the bar longer, pitching the bike further forward and making the centre of gravity further forward thereby helping get the front end down. Unfortunately, the wheel helps the bike to keep sitting up under forward momentum and not act like a 'brake', so the bike is more inclined to stay in it's wheelie. The only way to benefit from having no drag slowing forward momentum and have the bike more condusive to stay on its main wheels is make the bar so long as to be ridiculous. The only other option is to have a set of 'drag bike' bars that are so low to the ground as to not extend for a massive distance from the rear.

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Where the red 'wheel' is is about as far as you'd want to go.



The plain wheelie bar:

This is simply a bar, or loop that extends out towards the rear and stops the bike from flipping over. Unlike the wheeled bar, it creates drag. This drag, combined with a lessening of forward motion ie. hitting the brakes, makes the bike drop back onto it's intended wheels quite easily. The longer the bar protrudes from the rear, the further away from the bikes' centre of gravity having the ability to sit over between the two contact points. The further forward the centre of gravity is when it is sat on the wheelie bar, the more the bike wishes to get back down onto it's wheels. This is opposite to the wheeled bar, when you wish to have the centre of gravity between the two points of contact on the floor to sustain the wheelie.

The benefits of getting back onto the wheels is:

You can reapply throttle to gain speed again.
You can steer where you want to go.
You can counter any bumps on the surface by having full control.

Off road, especially on bumpy tracks, you want as much control as possible. The bumps in the track are already throwing you all over, any further complications that reduce control just makes things far harder.

A small flaw does appear on the plain wheelie bar on soft ground. The bar can act like a dagger, sticking into the ground causing an abrupt stop to forward momentum. Whilst this does facilitate getting back onto the wheels again, forward momentum has always been a plus regarding stability of a cycle design. Therefore, the design needs to be a compromise of how much drag it will induce. A picture here will further enhance my explanation.

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The red line represents the ground. The orange line shows a curved plain wheelie bar.

As you can see, the point where the wheelie bar from it's exit at the rear of the frame, in a straight line, would be the dagger approach.
By following the orange line, you see it curves rearward, increasing surface area and stopping the bar from sticking into soft ground. The amount of drag can be increased or decreased according to both the bend used and the material.





You pays your money, you takes your choice.
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Old Nov 10, 2012, 09:25 PM
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Great explanation I'm going to come up with something that's works but doesn't get in the way
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Old Nov 10, 2012, 10:48 PM
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Originally Posted by Rellik View Post
What is the best wheelie bar out and where can I get it?
Here's a couple I use Rellik, the big wheel one is made from the end of a 1/8th buggy front arm and aero wheel. The bar is cut and hammered straight and holes drilled up the arms and pushed into place. If the hole is the right size it won't need glue but you can use metal epoxy to hold it. The small alloy one is a Alleven one, I don't know if they are available yet. The vids I did of long wheelies have the rubber wheel. Works better on bitumen. Both of these seem ideal at not allowing the bike to overpivot and get the front back down easily if you get off the throttle.

http://www.rcgroups.com/forums/newat...anageattach&p=
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Old Nov 10, 2012, 10:57 PM
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Sorry Rellik trying to sort things
http://www.rcgroups.com/forums/newat...ach&p=23238077
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