its now a e-motorcycle

[deVries]

Me too Its my first go at welding ( apart from the loads of mistakes I made ), I hope it is solid for what Im going to be doing with it. The frame was built from scratch, the sump guard/bashplate is off of a offroad motorcycle.

That welding is superb. What method/equip are you using cause it looks really good. No beginner look, imo.

How did you do your alignment? Also, for the rear suspension how did you design it? Based on what?

Shoot some vids when you have a chance.

Thanks!

[gwhy!]

Me too Its my first go at welding ( apart from the loads of mistakes I made ), I hope it is solid for what Im going to be doing with it. The frame was built from scratch, the sump guard/bashplate is off of a offroad motorcycle.

That welding is superb. What method/equip are you using cause it looks really good. No beginner look, imo.

How did you do your alignment? Also, for the rear suspension how did you design it? Based on what?

Shoot some vids when you have a chance.

Thanks!

Thanks for the kind words,
The alignment of the main frame was easy, I just clamped the square tube to a flat surface and welded it up, I used a hole saw to cut the the hole in the top tube for the head tube to fit ( the size of the hole saw was just right and left about 1mm each side of the square top tube and the head tube was a nice tight fit into the hole. The welder I have is a very cheap gas-less 90A mig ( around £59 new ). the hardest part was the swing arm but still easy to get straight by clamping to a flat surface. The suspension came out really well and works very well ( it could do with a stiffer ( progressive ) spring ) but it is more than useable . I just modelled it on a normal motorcycle mono shock suspension . I will try and get some vid when the weather get a bit better, because I haven't made no body work for it yet so I dont ride it when its to muddy or to wet .

[GCinDC]

I used a hole saw to cut the the hole in the top tube for the head tube

wow, great idea.

the hardest part was the swing arm but still easy to get straight by clamping to a flat surface.

what's the swingarm made of? how did you make it?

[gwhy!]

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Its made from 40mm x 20mm x2.5mm steel, When I make another ( I have a new wider hub so it will need to be done ) I will do it slightly different to make it easier.

[cajunjay]

Awesome build gwhy

Any more pics or videos coming soon.....?

[GCinDC]

Its made from 40mm x 20mm x2.5mm steel

i'm still scratching my head...

so for example on the dropout, you cut out pieces, folded and welded the flap down?

how did you get the bend in the middle of the swingarm? or was that cut and welded there?

[gwhy!]

Awesome build gwhy

Any more pics or videos coming soon.....?

Thanks,
I have been meaning to get some video but I never seem to be prepared enough for when I go out on it . I will try to sort something out and get some vid.

Its made from 40mm x 20mm x2.5mm steel

i'm still scratching my head...

so for example on the dropout, you cut out pieces, folded and welded the flap down?

Yes.

how did you get the bend in the middle of the swingarm? or was that cut and welded there?

Yes I cut 3 sides of the tube bent and welded it.

[Whiplash]

WOW! The bikes looking great! you inspired me to build a frame similar to yours and just cover the sides with panels to hide the uglies...

Tha bike is awesome! WE NEED VIDEO!!

[Craigh85]

Any updates on this one, been dying to see it in action for ages now??

Craig

[gwhy!]

Any updates on this one, been dying to see it in action for ages now??

Craig

Sorry Craig, no videos
I found that the rear shock is not up to the job to really show what the bike is capable of i.e splats and dropoffs so I didnt feel that it would be worth a video ( I would have to re-make the rear of the bike to accommodate a much better shock ), I have not forgotten about this project and still do ride it occasionally but now I have found the bikes limitations all my attention is now on getting a full size trials bike with proper suspension up and running.

[Craigh85]

That's a shame ahh well gd luck with the next project.

Craig

[drewjet]

all my attention is now on getting a full size trials bike with proper suspension up and running.

I have been dreaming of a full size trials bike myself. Are you planing on a conversion or a all up self-build? Please make a build thread for it!

[gwhy!]

all my attention is now on getting a full size trials bike with proper suspension up and running.

I have been dreaming of a full size trials bike myself. Are you planing on a conversion or a all up self-build? Please make a build thread for it!

No this will be a conversion from a gas bike. I already have the bike

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[Craigh85]

Very nice. I would love to see some one remove the crank from the original transmission and fit an astro 3220 or this new 4 inch one that coming soon. What's the plans with this one? I will be watching intently

[gwhy!]

Very nice. I would love to see some one remove the crank from the original transmission and fit an astro 3220 or this new 4 inch one that coming soon. What's the plans with this one? I will be watching intently

I have had it running before but with a little 3kw turnigy, needless to say it was a bit underpowered so now I have a new plan but still running it directly with a different configuration of motor(s). I was also thinking about using the original transmission but this will be a last resort as it will take up a lot of space which means less room for battery's. I will try and post up whats going on with this one in this thread

[Craigh85]

What kind of weights in a striped rolling chassi ? It sure looks light.

[gwhy!]

What kind of weights in a striped rolling chassi ? It sure looks light.

its around 42kg, when I had it running with the small out runner with 10ah of battery it had a total weight of 51kg but this was a little to heavy for the poor old tiny motor.

[drewjet]

So what motor are you planning, how much battery, and what top speed?

What is the typical wet weight of a gas trials bike?

Will you be able to be lighter or about the same with your conversion?

Sorry for all the questions. but I have never done trials before, and it sure looks to be fun, and as long as you are not trying some of the really crazy stunts, it seems relatively safe, as the speed is not real high. There just isn't a lot of info on this forum, and I haven't got the time for other places.

[gwhy!]

So what motor are you planning, how much battery, and what top speed?

What is the typical wet weight of a gas trials bike?

Will you be able to be lighter or about the same with your conversion?

Sorry for all the questions. but I have never done trials before, and it sure looks to be fun, and as long as you are not trying some of the really crazy stunts, it seems relatively safe, as the speed is not real high. There just isn't a lot of info on this forum, and I haven't got the time for other places.

A modern ( newer ) gas bike will be a bit lighter than the one I have ( with gas engine) which is around 75kg-80kg ready to ride.
After conversion with around 30/40Ah worth of lipo it will be around 60kg ready to ride. Top speed will be around 22mph ( but I have a few plans to make it 2 speed and try to gear it even slower ) the plan is to use 2 outrunners on a common shaft ( If I can make it fit to save space) Im estimating about 7kw at this speed should be enough to have some serious fun. Its about one of the safest and cheapest forms of motor sport to get into and I love it. Its more of a personal challenge rather than competing directly with others and you only ride what you feel comfortable doing and your skill set. When I had it running before with only 2.5kw @ 22mph it was usable as a beginners bike but You need more power once you start needing to pop the front wheel over stuff.

[drewjet]

Thanks for the input, it seemed about what I thought, but far better to get info from someone who knows than me guessing. Do you really think you need 40 AH worth of battery? My uneducated guess would say that due to the low speed and not always being on the power that 15 to 20 would be enough, but again that is why I am asking as my experience level is zero.

I was thinking of an Astro 3220, as I have a spare right now, It is good for 7 to 10KW bursts so with an optical sensor from Burtie, I think would be the ticket.

Again thanks for your insight into this

[gwhy!]

40ah will be over kill to lug around on the bike and I will prob only use 10ah worth on the bike at a time which should be enough. Yes most of the time you will only be pottering around at about 5-10mph but if there is a long hill climb ( at full throttle ) with a couple of stop/starts on the way then this will really bite into the battery also the very short bursts of power needed for popping the front wheel over stuff even you are still only travelling at walking pace, these all add up. My bike in the OP would do approx 10mins of constant demanding trial sections with 10ah or travel about 6-8miles for normal offroad riding ( mx style ) with 10ah so even the trials stuff is very slow, its very intense on the batterys. Putting this into perspective when competing in a trial there are around 40 sections that are marked on and each section will be about 1-2min long everything else will be just riding offroad style.

[cyclesguff]

Hi,

I've just joined endless-sphere and am amazed at some of the builds. I'm very interested in your trials bike build. My beta rev3 is possibly going over to electric, this will be the first time I have done any e-bike/moto build so any advice and tips would be be greatly appreciated.

Stay upright

[gwhy!]

Hi,

I've just joined endless-sphere and am amazed at some of the builds. I'm very interested in your trials bike build. My beta rev3 is possibly going over to electric, this will be the first time I have done any e-bike/moto build so any advice and tips would be be greatly appreciated.

Stay upright

Hi and welcome to es,
umm rev3 to electric very nice, the rev3 has always been my bike of choice. I have the sherco as it was a very cheap bike to play around with and being a steel frame would be easy to weld lugs and stuff to if needed. The only problem with the rev3 is the petrol tank, being part of the frame it takes up valuable space. I am messing about with a "one mount fits all" universal fitting solution at the moment. Some tips: aim for a total weight of the bike ready to ride at about 60-65kg ( should be easy to do with the rev ) think about what the top speed needs to be ( aim for 25mph for 95% of trials stuff, if you can get it upto around 30 would be better for long climbs ). you need to be looking for a min 3-4kw power for easy route trials and 5-7kw middle route and 7kw+ for hard route stuff ( but this really depends on the weight of the completed bike) . you will get around 8 sections on a middle route and the commutes inbetween ( as long as the commutes are not to far/long ) on about 10Ah ( think about swapable batterys instead of carrying all the batterys on the bike at the same time this saves weight and unnessasary power wastage ) .

[cyclesguff]

Hi,

Thanks for the advice and the universal fit sounds very interesting. I was also thinking about the issues of the petrol tank and aluminium frame. The beta is a good runner and tidy bike, so it might be worth selling it and buying a gas gas, sherco non-runner as the basis for the project. I don't compete in trials, but am lucky enough to have an old quarry close to my house for pottering about. Noise can also be an issue, so a 'quiet' bike seems like the way to go.

[bzhwindtalker]

I started riding trial style stuff lately, I really like it! My next bike will definitely be geared more towards trial. However keeping pedals on a E-trial sucks :/ I feel like it limits the bike, but loosing pedals means loosing a lot of legitimity to ride on protected trails and do rock climbing on the seafront... Decisions, decisions..