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m66

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So... I'm the process of rebuilding my Greaser to, let's say more aggressive specs:
That will be motorcycle 21x1,85 front rim, 19x,2,5 rear rim.
Twin 220 rotors and double Magura MT5 calipers on the front
Single 203 rotor and MT4 on the back
All electric is out as you can see, and 1kW BBSHD is monted - current spacers will be changed for one that will allow me to mount bashguard from Acerbis underneath ;)
Lights may came back, or be placed on shelf for some time. There was independent 12V system for them.
Rear, bolted on, double shock suspension, front changed to one that will allow double caliper mount :D

And now some photos how it looked thru iterations:

It looked like this brand new
tSDmIiA.jpg

pSLddH2.jpg


After some changes:

Aew7Yth.jpg


SdcOHsa.jpg
 
Nice, makes me curious!
Are you planning to use same rear hub? How does this fork perform with the smaller flaws of the road surface?
 
Hi! Thanks mate :D
Nice, makes me curious!
Are you planning to use same rear hub? How does this fork perform with the smaller flaws of the road surface?

So regarding rear hub. It will be 5 gear Sturmey Archer, current one has 7 sprocket cassette, and motor. It's going away, I don't like derailleurs :D

As for the forks. heck yeah! 180 or 200mm of travel with 26" wheel with 2,8" or larger tire. That was real relief in comparison to stiff forks I was having at the start. You need to tune them to the speed and surface, and style of riding but they are doing the job. I was blown away by the difference, and little scared for some time before i learned again how to safely lean bike in the corner ;)
 
I am thinking of buying same forks while they are on discount. But was unsure of "sensitivity" of them.
Great idea with 5 gears SA. Planetary hubs are cool! I was looking forward exactly for that when asked you :)
I run Nuvinci on ebike i am building, and can strongly recommend this hub for electric build. You can shift this one under load, so you don't need to wait for motor to deactivate when you stop pedaling to switch the gear.
And you can get one pretty cheap too. So think about it, that could be a good option to go for :)
 
They are on constant discount on Aliexpress - i bought this set for... 109$ (more is robbery tbh) those are probably factory rejects from Zoom DH 1100 series, with sticker informing you, that those are not downhill forks ;) They lack preload - but this is fixable I think, I'm to lazy to do this, and this don't bother me a lot. Don't use rotors bigger than 180 with this one, forces are to big and fork is twisting - and that is scary like heck.
But they are doing their jobs, and are still working after 15 000 km of offroad, and on-road abuse withe speed exceeding 50kph. But the left one will soon need servicing.

Basically this is good fork, for this price is great, but you need to find his limitations and quirks, ans work with them. One of good things is that you can change stiffness/rebound mid ride. I was riding "stiff" on roads, "medium" on pavement, and "soft" off road - this one is so so... I weigh 90kg, bike is... 32 to 36 so 120/130 total, and I'm bottoming out 8 on 10 times.

I'm switching to DNM 8S double break set - V max of this build will exceed 60kph (I hope for 80 on flat) so I'm looking towards motorcycle and emoto parts.

Which NuVinci you are using? And with what engine :D I want NuVinci N171 if this SA RX-RK5 will die (I hope not, 2 up and 2 down with 120Nm of torque on the engine shaft will be awesome -BBSHD FTW!). I'm mounting engine cutoff (repurposed e-bike break lever) to the gear shifter as a "clutch" it will work, or it will shred my drive to pieces ;)
 
The main drawback of those forks for me is the absence of full fender mounts. It also doesn't seem like you can just drill the hole and use a nut-rivet in it either :)
 
yep, not really, you need to resolve to MX or desert sled style fender mounted to lower crown tree, or you need to fabricate mount that will attach to axel clamps.

Or you cans say "screw it" and go for pitbike front suspension when you have all the mount points already there :)
 
Some update. Space for the battery is insane :) this one will have huge range.

Fiddling with suspension geometry, and test fitting. This has future, and is way simpler than anticipated. Which is nice, but it mens that this will be hard to build properly :)

T8aGJLV.jpg

Of course this is only proof of concept. Final parts will be CNC aluminium not cardboard and random stuff ;)

"Tank" and seat:

B6eYkSL.jpg

kJUpyHO.jpg

H7etdjU.jpg


Half of front fearing:
S4Cvqvj.jpg


Happy new year Ladies and Gents ;)
 
If you manage to install two front brakes this will eliminate the fork's twisting problem. Then you could go with 203mm rotors.
You have so much power, why don't you remove the pedals and go throttle only? You could bolt pegs in place of the cranks, or turn both cranks in the same direction and secure them to the frame (so your feet are more forward), or you could fabricate floorboards (which I realize won't quite match the overall style of the build).
Also, you could probably bolt a threaded stem to the bottom shaft opening, you need to measure it to see what fits.
I like your cats too :)
 
If you manage to install two front brakes this will eliminate the fork's twisting problem. Then you could go with 203mm rotors.
You have so much power, why don't you remove the pedals and go throttle only? You could bolt pegs in place of the cranks, or turn both cranks in the same direction and secure them to the frame (so your feet are more forward), or you could fabricate floorboards (which I realize won't quite match the overall style of the build).
Also, you could probably bolt a threaded stem to the bottom shaft opening, you need to measure it to see what fits.
I like your cats too :)

It's non much power. It will be still still to slow for a motorcycle, but it will be something between bicycle and moped. I just need to reprogram it to have street legal, and "fun" modes (200km of range or 1,5h or fun). And I have too much experience with running out of power in unexpected places, to know that pedals in light constructions are life savers :). I love electric motorcycles, but with current state of battery technology I would not buy one. Engines are ok, but battery are still... well... garbage :)
 
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So... build continues. First rough prototype, almost all dimensions are wrong (I used some ...... 3d model of rear hooks as reference point...) but it's step in the good direction. Couple more mistakes and it will be shiny aluminium soon ;)

Work on the tank is going further. Also 18" rimm just came by a post with new 800mm aluminium motocross handelbars :)

uh4mcbb.jpg


Rear subframe, old rear rack bolted to aluminium extrusion in "tank" battery holder + soon to cut to size seat post mount.

RRGqDcU.jpg

SbYMwMx.jpg
 
Remeber - there is no such thing as "over-engineering", not everybody has to do the hacking/welding/butchering style bikes like me :21:
 
There was hiatus in the project due to work, ...... sub-frame and lack of ideas... and wheels. But... thanks to @SpikeFC i have half ot the set, and soon I will have full one :D Big thanks!

What I learned from this:

1) motorcycle rims on bike hubs sounds awesome... until you heard how much work it takes to put them together... but they still looks sweet as heck ;)

2) don't cheap out on primer and paint

3) you can put motocross tire on the rim using bike tools - this is borderline suicidial, it's taking half an hour but it's doable

4) pumping it with bicycle pump is not ;P

5) aluminium racks are making good sub - frames if you cut them good ;P
 

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