[Judeyramone]

What interests me in Rosko's photos is the shock mounts. Looks easy enough to convert a CB350 swingarm (if this is indeed one) to use non-clevis type rear shocks. Why don't more people do this?

 

[craig641]

My guess is because clevis type Works shocks are readily available. And unless you were trying every last trick to save weight there isn't a big reason to make the switch that I'm aware of.

Craig

 

[texmawby]

rosko,

who's set up was that? i'd be afraid something might leap up in that rear brake....like a stone from the gravel trap, and cause a bigger problem.

tex

 

[UngaWunga]

Yup, normally big openings in the brakes are covered with screens. Would be a good idea, but nice setup for a racebike.

 

[unit]

you say you won't b using the rear brake much, have you thought about using a smaller hub?
heres a cb350 i saw at the races with a hub that looks like it belongs on a cb100.

 

[Bateman147]

Not that I would advise anyone else to try this, but here's some "experimental" lightening on a CB175 rear hub. Wouldn't want to go anywhere near this far on a front backing plate. This is just off the mill - I'll be sure to smooth carefully inside the brake arm boss at a minimum to remove any stress risers. It is very definitely weaker than stock, but probably still more than strong enough for a rear brake on a 200lb race bike. Still - I'll be inspecting that one after every race for signs of cracking or deformation. I didn't take a pic of the backing plate turned over, but every slot misses every web.

I don't think it really lost much weight. There is more variation in stock castings than the amount of weight I removed from the brake drum drilling the rim between the spokes. But it sure looks cool.

Bateman

 

[texmawby]

and just think, when the races are over you can strain the pasta you are cooking trackside.

impressive milling for sure!

cheers,

tex

 

[joe c]

tex, thats hilarious.

christian, no way youll get those numbers. it takes a metric ton of tuning and $$$ to get that. i have never heard of a stocker making more than 32. that was rabbies cb tuned by pete, and i talked about that bike with rab quite a bit when he had it, by the way. if im building it on your budget. 28 would be a good number to get. you can always buy an sl rear hub. smaller, lighter. and they bolt right up. one other thing, to really make stuff look trick, like that, you need a milling machine and rotary table. then a deburring tool to clean everything up. i gave my machined backing plate to jungle joe since when i sent it out i had forgotten i have a 360 rear. if you want to save more weight back there, turn the liner of the drum down. its cast iron. the time spent on the alu isnt worth while. takes less time to chuck it up and spin out some of that cast iron. heres a pic of jerseys.

other wise, i tend to agree with the consensus here.

that 100 rear hub is cool if not also unsettling.

also, i heard about your "shaving" accident. we're going to have to have a talk about that.

 

[joe c]

and really, i'd be more concerned about side loading on the hub. as opposed to any kind of straight line forces. i think youde be surprised at how much stress is put there. i turned mine. the flange and the hub itself. but only a tiny bit. really enough to clean it off nicely.

 

[Bateman147]

I like it - "The Pasta Strainer" has a nice ring to it... Too bad it's on a Honda and not on a Duc. "The rice colander" just doesn't have that nice ring...

I completely agree on the hub forces - think about how much side loading is on the hub in addition to radial forces in the transition from full lean left to full lean right. Then think about hard cornering at fulltiltboogie and hitting a pothole in the track. Not to mention trail braking while cornering and hitting bumps. Be careful where and how you drill in hubs!

Then look carefully about where and how the loads get from the rim to the bearings all from one side of the hub - and be prepared to be impressed that it holds up at all. Then get scared about all the stress risers that are present in a stock casting...

No matter what you're drilling/milling in you'd better be thinking about load paths and stress risers.

And of course don't do any of this anyway - your kids will have three eyes and your nads will fall off and your cats will impregnate your dogs and your wife will run off with the neighbor's goat and there'll be toads falling from the sky - total pandemonium.

Having a lathe, milling machine and rotary table in the shop is dangerous to your racebike parts - they end up looking like pasta strainers...

None of it loses more weight than a good dump before racing anyway. In my case it's purely to look bitchin' and be able to maintain my status as #1 cheatin' bastard. One of the other mad scientist fabricators out here loves to say "yes I made it, yes it's damn cool, no you can't have one..."

Bateman

"I ran over
some old lady
one night at the county fair,
but I didn't
get arrested
because my dad's the mayor..."

 

[joe c]

fill your tires with helium. weigh your boots. none if it makes a difference if you dont twist the throttle. facts are facts, uncool looking, heavier bikes, still run 136's at summit. if you cant run a 136/138, youre not going to win. its not the bike, its in your wrist.

 

[Bateman147]

I'll take "Twist the throttle, win the race and look bitchin' doing it to boot for $500 Alex..."

Joe's right though - this is all just whacking off. If you're not already winning you really should spending your time/effort/sheckles on riding and learning to go fast. At an absolute minimum your bike preparation should be <perfect> before you start drilling holes in things.

But if you can do both...

The absolute best is to be getting shit for winning "because your bike is so fast and well prepared," borrow a shitbox bike, be told "you'll see - you'll be midpack at best on this bike," balk the start because the bike is truly a shitbox and go into T1 last, end up passing everyone and win the race by half a straightaway, then be able to cruise up to the bike owner after the race and say "You're right - this bike is kinda slow..."

That is exceptionally satisfying.

Bateman

 

[joe c]

im not saying ride a shitbox. build a good basic bike, learn that the first weekend out, can be your last weekend of the season, (ask paul). learn the track. learn the bike. then go nuts. make improvements to the bike as you realize its limiting you. many people have a good formula for building a basic bike. its been done since the cb350 came out. im all for building a bitchen bike, but when you barely have 2 weekends of racing under your belt, and you have a rolling chasis, and not a ton of ¢¢ for stuff, best bet is to be getting shit together. before cracking that cover the night before you leave for vir, and realize you need another. like bill says, only about 4 months before vir. in 2.5 months, you should be very close to having a bike that will be ridable. so as not to be rushing. my the end of january, mid feb at the latest, you need to know you can make vir.

go through the motor. go through the frame. go through the suspension. most importantly, twist the damned throttle wide open every chance you have.

 

[joe c]

jerseys rear, i mean this is her back brake.

get those brake shoes drilled too.

 

[busapilot]

quote:Originally posted by joe c

jerseys rear, i mean this is her back brake.

Love it! I mean her back brake.

I will be running the rice strainer this season for as long as she holds. Let's call it my way of encouraging everyone to be in front of me so nothing hits you when it falls off my bike.

 

[crazypj]

I've only done the front so far, don't know how heavy it as before I started but it's 4.5lbs with bearings.
I've got some idea's for rear and I am going to machine front and rear brake plates, just cos I can. [)]
I am going to do some internal modifications to maintain strength of brake plate, something that used to be done in 1950's
Front hub

hub before drilling holes on spoke flanges

This is what I dun to sproket cover (CB360)

 

[busapilot]

Beautiful, but not sure that can still be referred to as a sprocket cover?



Ok, so what are the chances to mod the rear hub from a CB100:
a) to take new bearing with CB100 outside diameter and CB350 inner for 350 axle?
b) to drill the CB100 hub to accept a standard CB350 bearing and axle?

And could you use the same sprocket from a CB350 on the CB100 hub (with minor mod)?

 

[Mercury Kid]

Here's a progress shot. Shaved a double quarter pounder with cheese so far. And that's pre-cooked patty weight.

 

[RondaDAHonda]

Looks Good how do you drill them with a press or by hand??

Also i was wondering if anyone was looking for the measurements of the CL100 rear hub bearings cause mine is apart right now just let me know..

Red

 

[unit]

busa pilot i've got cb100 and 350 hubs but the only problem is there in box's because i've just moved and the shed ain't built yet.
i'll go have a look for them now.

mercury kid i've done the same thing with my 350 sprocket cover it looks good once all filed cean.

crazypj those look great, would you mind showing the inside of the hub im interested in seeing how you fitted the mesh.