Light dirt bike, QS 120 70h motor, custom steel frame

CEtFAIz.jpg


hwXccLE.jpg
 
trazor said:
Great progress! I'm curious about which method you use to bend tubes.
And the tube notching is perfect how you did it?

there's a machine shop very close to my house about 1 block away. i just print an actual size template of the bends and he does them on the steel pipe using a manual pipe bender w/ roller die. i'll try to get a pic

as for notching i have an earlier post about this. just print out the template on sticker paper

Overclocker said:
3ae3wY7.jpg


TGFE1fO.jpg


http://cq.cx/tubejoin.pl

finally the holidays, i think i'll have some time to work on this
 
Overclocker said:
trazor said:
Great progress! I'm curious about which method you use to bend tubes.
And the tube notching is perfect how you did it?

there's a machine shop very close to my house about 1 block away. i just print an actual size template of the bends and he does them on the steel pipe using a manual pipe bender w/ roller die. i'll try to get a pic

as for notching i have an earlier post about this. just print out the template on sticker paper

Overclocker said:
3ae3wY7.jpg


TGFE1fO.jpg


http://cq.cx/tubejoin.pl

finally the holidays, i think i'll have some time to work on this

I use the sticker method with an angle grinder but neved reached the level of precision you show in your pictures. I usually have a 1mm gap in some places.
 
this is actually my first time to notch so i'm surprised that it worked as well as it did :lol:

maybe you just have to compensate for the thickness of the pipe. the template generated is really for a theoretical zero-thickness pipe.

IVHKf7j.jpg


"footpegs". cheap VP Components pedals hoping they break off in a crash and not damage the frame :lol:
 
trazor said:
Overclocker said:
trazor said:
Great progress! I'm curious about which method you use to bend tubes.
And the tube notching is perfect how you did it?

there's a machine shop very close to my house about 1 block away. i just print an actual size template of the bends and he does them on the steel pipe using a manual pipe bender w/ roller die. i'll try to get a pic

as for notching i have an earlier post about this. just print out the template on sticker paper

Overclocker said:
3ae3wY7.jpg


TGFE1fO.jpg


http://cq.cx/tubejoin.pl

finally the holidays, i think i'll have some time to work on this

I use the sticker method with an angle grinder but neved reached the level of precision you show in your pictures. I usually have a 1mm gap in some places.

It's much easier with a die-grinder or rotary tool. Tough to get right with and angle grinder.
 
nice work :thumb:
As a small hint in terms of form stability of the frame, i would weld something like the "X" as done on LMX frames near the head tube to make it stiffer.
And i also would weld another tube between motor and battery to have upper and lower tubes connected.
 
madin88 said:
nice work :thumb:
As a small hint in terms of form stability of the frame, i would weld something like the "X" as done on LMX frames near the head tube to make it stiffer.
And i also would weld another tube between motor and battery to have upper and lower tubes connected.


m2Af0c9.jpg


thanks. yes definitely going to add bracing and gussets

i actually have 2 separate battery packs in there w/ some space in between. so i'll slip some flat bars in between (GREEN LINES)

i'll also gusset the crossmembers off the upper shock mount

as for the RED LINE i'm still thinking about it... it's probably not needed? what do you think?
 
Overclocker said:
madin88 said:
nice work :thumb:
As a small hint in terms of form stability of the frame, i would weld something like the "X" as done on LMX frames near the head tube to make it stiffer.
And i also would weld another tube between motor and battery to have upper and lower tubes connected.


m2Af0c9.jpg


thanks. yes definitely going to add bracing and gussets

i actually have 2 separate battery packs in there w/ some space in between. so i'll slip some flat bars in between (GREEN LINES)

i'll also gusset the crossmembers off the upper shock mount

as for the RED LINE i'm still thinking about it... it's probably not needed? what do you think?

Looking sweet! Sometimes quality takes time!
 
Awesome build!
Apologies if I missed it, Is the whole frame water pipe? Or just the head-tube?
If not what tubing have you used?

Thanks
 
Chambers said:
Awesome build!
Apologies if I missed it, Is the whole frame water pipe? Or just the head-tube?
If not what tubing have you used?

Thanks



head tube is galvanized water pipe :lol: but dipped in hydrochloric acid to remove the zinc (not good to weld zinc)

the smaller tubes are 1/2" nominal ERW. actual OD about 20.8mm. wall thickness about 1.8mm
 
Definitely do the head tube bracing (I would probably do it out of plate instead of tube myself) and a couple of other cross braces for triangulation
- I would use tube for this not flat bar as flat bar is only strong in one direction.
1.8mm wall is heaps. 1.2 would probably be fine.

Keep it up it's a cool project.
 
Overclocker said:
as for the RED LINE i'm still thinking about it... it's probably not needed? what do you think?

The red tube shows what i meant as second, but i also think if you weld the green tubes it should not be that important anymore.
 
Chambers said:
Definitely do the head tube bracing (I would probably do it out of plate instead of tube myself) and a couple of other cross braces for triangulation
- I would use tube for this not flat bar as flat bar is only strong in one direction.
1.8mm wall is heaps. 1.2 would probably be fine.

Keep it up it's a cool project.

1.2mm would be on too thin side. Especially at placed were next to weld. Pipes are structural steel.
I use 1.5mm ant it's on very thin side.
2mm or 1.8mm is better.
It's easier to work with 2mm, 2.5mm or 3mm compared with thinner.
Of course thickness has additional weight.
 
i picked 1.8mm wall thickness because thinner is very difficult to weld w/ my 0.9mm fluxcore wire, at least w/ the machine i have. anyway i just picked up a co2 tank. let's see if i could weld 1.3mm wall w/ MIG. i could probably get away w/ using thinner wall for the saddle bracket

IIaByMP.jpg


[youtube]AcRJutbmjss[/youtube]

ydRI0WB.jpg


in other news, my crappy DNM shock Decided Not to Move :lol: had to do a schrader valve mod to pump it up again
 
Was the DNM rear shock over pressurised? Ive had that on an RCP2. All the others seem to be spot on.
 
Overclocker said:
i picked 1.8mm wall thickness because thinner is very difficult to weld w/ my 0.9mm fluxcore wire, at least w/ the machine i have. anyway i just picked up a co2 tank. let's see if i could weld 1.3mm wall w/ MIG. i could probably get away w/ using thinner wall for the saddle bracket

IIaByMP.jpg


[youtube]AcRJutbmjss[/youtube]

ydRI0WB.jpg


in other news, my crappy DNM shock Decided Not to Move :lol: had to do a schrader valve mod to pump it up again

Oh please do a guide/video on that mod. There is one in russian that I don't understand anything and skips lot of steps. We need the definitive guide to mod the RCP2 with schrader valve. I know it is a PITA to disassemble it again but.... it is for the community :)

As a side note.. I use 2mm 5/8in structural steel pipe on my bikes. I beat them a lot and didn't have any damage on the frames. (I damaged forks, handlebars, sprockets, controllers, but not the frames :lol: )
 
Sean9002, i think it lost pressure, which kept the rebound needle from backing off the orifice, thus the super slow rebound. full diagnosis soon

trazor, sure. actually i haven't filled it w/ oil yet, that's the messy part. will make a video soon. btw what's your complete frame weight without shock and accessories?
 
Overclocker said:
Sean9002, i think it lost pressure, which kept the rebound needle from backing off the orifice, thus the super slow rebound. full diagnosis soon

trazor, sure. actually i haven't filled it w/ oil yet, that's the messy part. will make a video soon. btw what's your complete frame weight without shock and accessories?

Great!
Unfortunately I've not weighted my frames (v1 and v2). I'm planning to paint them soon and that is a good opportunity to weight them. I will update OpenEmoto thread when I have the numbers and of course pictures of the paintjob.
The numbers I've now is v1 with 720Wh battery: 40KG, v2 with 100Wh battery 50KG. v2 is taller, longer and the headtube is machined and thick instead of 1 1/2 inch tubing (v1 uses standard headset and v2 uses semi integrated)

Keep going! you have made great progress in the last weeks.
 
Back
Top