Taking things too far, again.

[ygolohcysp]

Hello! First off, it's great to see KR back up.

It saddens me to see that my redoing of the thread where I build a crf150f supermoto miniGP bike is once again returned to a mess of photobucket link problems, and the more recent posts are gone. I will perhaps go back and redo those picture links again. However, I'm moving on to an even more impressive work of taking things too far.

The pocket bike I built, modifying everything including frame, forks, brakes, engine, swingarm, and adding a Honda 954RR rear shock is an absolute blast to ride. It handles ridiculously well. However, it's a pocket bike. It's too small to be comfortable on (specifically actual physical comfort/fatigue, it's actually really good for comfort in respect to confidence). I like the idea of a grom sized bike, but there is too much wrong with the grom from the get go as far as ergonomics go. This year, risemoto.com is beginning to import bikes from Ohvale, which look remarkable! But, they seem to be the same size as my pocket bike, and way too expensive.

What's a racing addict to do? Well, build his own bike, of course.

My plan so far is to source some Honda Grom wheels and forks. I've already had a friend donate the rear shock from an R6. I've been analyzing the geometry of what makes sport bikes, and my pocket bike, work much better than a grom. I'm learning how to do 3d models in Fusion 360, and how to "build assemblies". I intend on getting a really decent TIG welder (to compliment my home hobby machine shop). I'm designing a frame that will incorporate correct rake/trail angles, that will have adjustable rear sets and the seat in the correct spots, and I'm going to make it out of aluminum.

There are a variety of racing slicks in all compounds available for the 12" wheels. There are Ohlins kits available for Grom forks. And, there's a 190cc Daytona engine out there just dying to go to work in a complete custom build Grom sized SS bike.

If you have any suggestions, let me know. If you have any concerns, let me know. If you have any parts, let me know. And if you want to take out life insurance on me, well, maybe don't let me know.

Oh, and if you know how to mock up shapes for making fiberglass fairings, hit me up. Even if only good enough to make molds. If I have molds, I could feasibly learn how to make my own out of carbon fiber. But then, this bike will be used and abused, so I kind of need to make it so it'll survive crashes.

Cheers!

[steves]

[Kreylyn]

Oh, and if you know how to mock up shapes for making fiberglass fairings, hit me up. Even if only good enough to make molds. If I have molds, I could feasibly learn how to make my own out of carbon fiber. But then, this bike will be used and abused, so I kind of need to make it so it'll survive crashes.

Cheers!

This... I know a simple way.

4 way stretchy cloth material and a staple gun.

Use wood to build a temp sub structure. Doesn't need to be pretty, it's just going to hold the cloth. Stretch the cloth over the wood, pull around edges, staple to the wood.

Once you have the cloth in the shape you want, apply resin directly to the cloth, let set up about 20-30 mins. You want it no longer sticky, but not fully stiff/hardened.

Remove the piece, pull the wood out. Allow to finish setting up.

You now have the base piece to layer resin and fiberglass for making the part.

This is the basic process of how we make anything from seat pans on custom bikes to custom consoles and parts in the autos at the upholstery shop.

Krey

[shpielers]

Major bummer your posts were lost, you did an amazing series of detailed write ups.

You racing next spring? (Or have winter season?)

Good luck with the next round of mods

[ygolohcysp]

Kreylyn, that's awesome. I'll have to remember that.

shpielers, the post wasn't completely lost. Just redoing the picture links to Imgur, and the last post or two about the new carb with the fuel pump. I absolutely plan on racing next spring, even if I have to just do maintenance on the current bike. But for now, I'm out of commission. I had shoulder surgery about 5 weeks ago. That's why I'm in the planning and learning cad/cam phase right now.

I do have some grom forks on their way to me now, along with the bottom triple tree and new bearings. Once I get those, I can size the tube for holding the steering bearings (in the cad/cam). I may still end up making my own stem and lower triple, as the stock one is iron or steel.

If I can get the TIG welder, then my current plan is to take something like .125 or .186 thick 4" OD aluminum tubing, and either build a roller or a form for the press to squish it down to about 1-1.25" thick and closer to 6" wide. Then cut, bend, and weld to form a very sport bike ish perimeter frame. Add gussets where needed. Boom.

[buffalobill]

Whatta ya talkin about?

Ok, I did a google search for crf150f supermoto miniGP
Got this video:

https://www.youtube.com/watch?v=bjmKZopMOLg

[ygolohcysp]

Ok, I did a google search for crf150f supermoto miniGP
Got this video:
https://www.youtube.com/watch?v=bjmKZopMOLg

That was a crf150r. To be fair though, I was putting out about as much power with my air cooled 2 valve 150 motor, which is why my friend and I kept having reliability issues. That, and downshifting 3 gears at a time sometimes. Here's a video of the last session I did on the last endurance race I did with that bike.

https://www.youtube.com/watch?v=ENX-xLvUMhI&t=1000s

[Lunatic]

Psychology,

I feel your pain as I too am rebuilding my B12 thread that got lost in the server crash.

On another note, it's good to see other machinist, welder, fabricator hobbyists out there. I worked at a place that had a CNC laser cutter, CNC press brake and lots of aluminum welders. While I no longer work there, I too have been purchasing some fabrication items for my garage. It takes time and money, that's for sure.

I like your ideas and can't wait to see them come to fruition. I like unique and different. I think the Grom wheels look far better then say, the Ruckus wheels.

I look forward to your build thread.

[ygolohcysp]

Psychology,

I feel your pain as I too am rebuilding my B12 thread that got lost in the server crash.

On another note, it's good to see other machinist, welder, fabricator hobbyists out there. I worked at a place that had a CNC laser cutter, CNC press brake and lots of aluminum welders. While I no longer work there, I too have been purchasing some fabrication items for my garage. It takes time and money, that's for sure.

I like your ideas and can't wait to see them come to fruition. I like unique and different. I think the Grom wheels look far better then say, the Ruckus wheels.

I look forward to your build thread.

Thank you. I've noticed you're rebuilding that thread. I may yet follow in your footsteps in that. Not sure yet.

So, I have the R6 shock, the Grom forks and lower triple, and new steering bearings. I'm fairly certain at this point that I'm going to make a new lower triple because the stock one is iron or steel. I'll have to make a new stem, cause it's welded in. I'm debating on whether or not I want to make the triple trees have pockets so I can make offset inserts to make the fork tube/steering stem offset adjustable, or if it would be easier to just make a couple sets of triple trees.

I'm currently reading up on chassis design, particularly the angle of the swingarm, chain, antisquat, moment arms and rotational torque from acceleration and braking. I figure the pocketbike works ridiculously well, so I'm going to take measurements of all the points on it to see what numbers and angles it has. Do the same with my buddy's race prepped R6. Study all the numbers, then start plotting the points that are known about the bike I'm building, like tire sizes, fork angle, axle locations, swingarm angle and length, swingarm pivot location, rearset and seat location, and then sort of connect the dots with the frame.

Anyway, here's the start to the bike:




Okay, this bike will be for racing, but building it won't really be race related. Should I keep this going as a build thread, or put it in the non katana forum?

Anyway, here's the beginning to my bike so far, plus the new bearings I have.

[shpielers]

My $.02, leave it here

[ygolohcysp]

So, physical therapy is annoying and tedious. I'm making a little progress every day, but in the wise words of someone I've probably never met, "I WANNA BE IMPATIENT NOW!"

Anyway, I've measured and done mock ups of the pocket bike and a race prepped R6. Studied lengths, proportions, angles. I've come up with a design that's hand drawn using drafting tools. I still plan on potentially putting it into CAD software, just because.

I've also started collecting some raw materials. I have what I need to make the triple trees and stem. I'm seriously considering making the fork offset adjustable with the triples. I guess I'll try making the inserts first, and if I can get those good enough, then I'll do the triple trees to accept them.

If only I could lift the vice and or rotary table onto the mill. Oh well, I'll get there.

[92xjunker]

Time for an overhead chain wench.....

[Lunatic]

Time for an overhead chain wench.....

I think you meant winch.

[92xjunker]

He could use a little of both.......lol

[ygolohcysp]

I wouldn't mind having a shop wench that could do some winching.