Topic: CB550 Cafe Interceptor - Gentleman's Roadster

[calj737]

All settled then, Jim. You're doing a Burnt Copper/Orange 650 Hybrid. Leave it to a Democracy to determine your fate and activities. Please hurry up and post some more progress. The anticipation is killing me! 

[754]

 I want Jimmy to do a 750 next...failing that ..a flattracker seeing as he has a track close by and another 3.5 hours away.... or a  street legal tracker..

[RAFster122s]

Excuse me for my ignorance, but why bother with swapping a 650 into the 550, why not just use the 650?  Is the geometry so much different, or is the frame really heavy?

Yes, the geometry IS that different. 
The 650 -- especially years 1980-82 is essentially a cruiser.  The 550 handles much better.  The 650 engine however has an approximate 15+ hp increase plus torque stock -- that's cheap power -- with the same weight.  This can be increased with an overbore kit, porting and a cam.

Is the '79 still an upright frame design...the cruisers I really hate the looks of and wouldn't consider. The  earlier I might.  But, popping a 650 into the frame isn't that much rocket science and some of the electrics spell complication and if they go bad, then the replacement is very costly. So, a hybrid requires some fabrication. I liked Paulage's hybrid more than a few of the recent variants.
I think Paulage was the first on these forums to chart the waters but, he hasn't been on the forums (that I am aware of) for several years now. So, you can't ask him questions about the conversion.

[SOHC4 Cafe Racer Fan]

Excuse me for my ignorance, but why bother with swapping a 650 into the 550, why not just use the 650?  Is the geometry so much different, or is the frame really heavy?

Yes, the geometry IS that different. 
The 650 -- especially years 1980-82 is essentially a cruiser.  The 550 handles much better.  The 650 engine however has an approximate 15+ hp increase plus torque stock -- that's cheap power -- with the same weight.  This can be increased with an overbore kit, porting and a cam.

Is the '79 still an upright frame design...the cruisers I really hate the looks of and wouldn't consider. The  earlier I might.  But, popping a 650 into the frame isn't that much rocket science and some of the electrics spell complication and if they go bad, then the replacement is very costly. So, a hybrid requires some fabrication. I liked Paulage's hybrid more than a few of the recent variants.
I think Paulage was the first on these forums to chart the waters but, he hasn't been on the forums (that I am aware of) for several years now. So, you can't ask him questions about the conversion.

The 1979 is definitely more upright than 1980-82 cruiser-oriented models.  The good thing is that all of the 1979-82 engines drop directly into a CB500 or CB550 frame.  You only have to remove the oil sump, filter and valve cover to install/remove.  650 electronics can be swapped into and mounted to the CB500/550 frames, too.  Not too much needed for that.

Paulages super hybrid motor required a LOT of finesse shoehorning 750 sleeves into the 650 cylinder.  They overlap and you have to machine the sleeves and block material precisely (and it looks fairly complicated).  That said, he probably made way more power than the 674cc kit, but at the cost of MANY more brain cells. I did try to ask him about it (no success) so I decided to go with a much easier solution via the Dynoman 674cc kit using stock 650 sleeves.

[HondaMan]

Excuse me for my ignorance, but why bother with swapping a 650 into the 550, why not just use the 650?  Is the geometry so much different, or is the frame really heavy?

Yes, the geometry IS that different. 
The 650 -- especially years 1980-82 is essentially a cruiser.  The 550 handles much better.  The 650 engine however has an approximate 15+ hp increase plus torque stock -- that's cheap power -- with the same weight.  This can be increased with an overbore kit, porting and a cam.

Is the '79 still an upright frame design...the cruisers I really hate the looks of and wouldn't consider. The  earlier I might.  But, popping a 650 into the frame isn't that much rocket science and some of the electrics spell complication and if they go bad, then the replacement is very costly. So, a hybrid requires some fabrication. I liked Paulage's hybrid more than a few of the recent variants.
I think Paulage was the first on these forums to chart the waters but, he hasn't been on the forums (that I am aware of) for several years now. So, you can't ask him questions about the conversion.

The only thing I can think of to add to it is: the 650 is geared low, real low, for the power it makes. So, consider using either the largest front sprocket that will fit, or lose a few teeth on the rear one, to make it seem less "GP" than the 550 it replaced.

...unless you're into GP riding on the street!

[SOHC4 Cafe Racer Fan]

That's an interesting piece of intel.  Will have to consider sprockets . . . .

[FunJimmy]

Weather is getting better.
Looking forward to some Hindle thunder.

<a href="Not a valid vimeo URL">Hindle Exhaust - CB550[/url]

[SOHC4 Cafe Racer Fan]

Weather is getting better.
Looking forward to some Hindle thunder.

Thank you kindly for that Jim.  I have something to look forward to now!!

[FunJimmy]

Had the Interceptor out for a short shakedown blast around the neighborhood and kept hearing an annoying rattle & buzz.
Closer inspection revealed the failure. Front chain guard mount fatigued and broke. I guess anodized aluminum isn't the ideal material for a chain guard.
I even had a funky Teflon glide incorporated too.   

So what should the next gen chain guard be made out of to prevent future failure?

[Retro Rocket]

Rubber mount it....

[SOHC4 Cafe Racer Fan]

Wow.  That plastic/delrin or whatever inner liner is trick.  I think Mick is on to something with rubber.  Maybe some rubber grommets between the chain guard and the mount points as vibration dampers. 

[MCRider]

Had the Interceptor out for a short shakedown blast around the neighborhood and kept hearing an annoying rattle & buzz.
Closer inspection revealed the failure. Front chain guard mount fatigued and broke. I guess anodized aluminum isn't the ideal material for a chain guard.
I even had a funky Teflon glide incorporated too.   

So what should the next gen chain guard be made out of to prevent future failure?

I'm crushed. I loved that chain guard. Would the next thicker material do it?

I bot some blanks for making one compliant with ECTA rules. Pretty thick aluminum stock. I'll find the thickness from their website.

Found it, .125" aluminum

http://www.1st-to-the-finish-line.com/products/chain-guard/universal.html

[FunJimmy]

I'm crushed. I loved that chain guard. Would the next thicker material do it?

Thanks Ron,

I'm bummed too but Gen II will be better.
The aluminum extrusion I used didn't come in a thicker gauge and anodized aluminum will always be susceptible to fatigue.
It's not a matter of "if". It's a matter of when.

This time around I'm going to try Kevlar reinforced carbon fiber.
Kevlar is used to stop bullets. It should be strong enough to survive the Interceptor. :-)

Mold ready for the layup!

[754]

For now just use a triangular bracket ,lay it over and use 2 countersunk bolts on the inside..
 When you come up here, bet we could build a bulletproof version.

[RAFster122s]

Jimmy,  I have some blue fiberglass fabric that has an aluminum layer built in... It is hard to get now. It is pretty stiff material.  Does not like to curve in compound directions and I'm not sure what it would do for a 90 degree turn. Likely to need to be cut.
I forget the name of it now...

I have some in yellow and blue.  Much less in blue.  It has an interesting look to it...

David

[FunJimmy]

FunJimmy's 5 layer drip!

3 layers of carbon and 2 layers of Kevlar shoved tightly into the mold. Anticipation.......

[Retro Rocket]

Carbon fiber and kevlar are very strong , stronger than the aluminum for sure, where they fail easily though, is under compression, you will have the same problem where the carbon/kevlar parts are bolted too the swingarm, I would have put some stainless inserts in between the sheets before adding the resin to reinforce where they bolt up... .

[FunJimmy]

Carbon fiber and kevlar are very strong , stronger than the aluminum for sure, where they fail easily though, is under compression, you will have the same problem where the carbon/kevlar parts are bolted too the swingarm, I would have put some stainless inserts in between the sheets before adding the resin to reinforce where they bolt up... .

Good point Mick. I was planning on using one of those fancy seat bolts with a couple of rubber washers to eliminate vibration. Honda uses them to mount plastic fenders.

[RAFster122s]

The stuff I am referring to is Hexcel Texalium. www.carbonsales.com has some photos of it. It doesn't capture the reflsection in sunlight.  There is a new fabric only available in silver that is made by composite.jp 
They make it in other colors but it is not commonly available, the silver is.

Since Texalium it is not capable of bending at 90 degrees, being a 2*2 3k twill it is difficult to fabricate a part like yours without it being cut. It is very pricey and hard to find since they stopped production a few years ago. It is a 6-8 ounce fiberglass cloth with a dispersion coating of aluminum using various gases to provide the color.
The new stuff is called Alumitex, not sure of its drapability. 

BTW, kevlar has great wear resistance but is bad at impact strength, only having about 30% of its strength. So, for a sliding impact it is great, but direct impacts it is still strong but, only about 30% of its usual strength.

David

[FunJimmy]

Carbon/Kevlar vs Aluminum

Let the cutting begin!

[Godffery]

 You gun'a make the tab up front wider this time?

[FunJimmy]

You gun'a make the tab up front wider this time?

Probably not. Shouldered bolt with rubber washers up front.
The carbon/Kevlar is a lot lighter and stronger than the aluminum.
Fatigue shouldn't be an issue.

[knowsnothing]

Fatigue shouldn't be an issue.

Famous last words    Looks fantastic, can't wait to see finished product.

[akabek]

Is it done yet?

[SOHC4 Cafe Racer Fan]

Is it done yet?

There's always a comedian!