Topic: '78 CB750k conversion to cafe racer (yes, more issues)

[Owned]

Absolutely, no question.

Also, the new 17T front sprocket arrived today with the new chain. I put everything on, but in the excitement forgot that the link supplied with the chain is a rivet style link, and I had ordered a clip on link which is being shipped separately. Will have to wait for that before closing everything up. This is a RK RX-ring 530XSOZ1 racing chain that I put on. I made sure to get a lubricant that was O-ring friendly.

In the meantime, when I put on the outer nut on the final drive shaft, I lightly tapped the tabs of the washer that grips the outer nut into place, and when I did that, I noticed one of the tabs developed a scored wrinkle.. is this okay? Or should I replace this washer?  Only three of those tabs fit in place, the others were not aligned. If you blow up the last picture, the shiny line on the tab below and to the left of the sun symbol is the wrinkle itself.

Looking at the pic showing your front sprocket, it appears that your yellow stator wire is broken...

[deafcaferacer]

Looking at the pic showing your front sprocket, it appears that your yellow stator wire is broken...

yikes, it really does look like it's broken, but it isn't.  That does look like a frayed end of one of the stator wires, not sure what makes it look like that. Thanks for the heads up though.

[deafcaferacer]

Well I got my pipes back from the sandblast company, polished them up and doused in WD40 and tried to put them on before finding the exhaust flanges wouldn't clear the frame, so I couldn't just slide them onto the pipes, they had to be put between the frame and ports and I engaged in a lot of wiggling with the pipes and shouting imprecations at the bike for a while before I figured out that I could shim the flanges wider open with a pair of washers, and bam, the pipes slid on just like that.

[deafcaferacer]

And so I took her out on a test run. Rode around for 5 minutes came back and checked for any kind of leaks, and my heart sank- it leaked oil at the exact same spot, but a much smaller leak. I removed the sprocket cover and found a hairline crack that I had missed (see pic attached, just above the 6th link, counting from the top).

My question here is: do I need to drain all the oil again (just filled with brand new 10w-40 castrol) before I apply JB bond over the small crack I missed? It doesn't leak when engine is cold, but I know surface prep is everything, and I risk fouling the oil inside when using acetone, applying JB bond, etc. Or is that too small of a deal?

[seanbarney41]

you should be fine dude...not much cleaner is gonna get in through that crack and if it does you are gonna change your oil in 1500miles anyway, right?  I used brake cleaner to clean after roughing up the area with a file and course sandpaper on a much worse crack.  The JB has been holding just fine for several years and tens of thousands of miles...

[deafcaferacer]

THE DAY THE ARSE RAPE FAIRY CAME EAST

So what do I do after finding a small leak in the case but brilliantly decide to go on another test run? There I am putting her through her strides and all seems fine, then I ram the throttle and everything just dies down. I pull over and pop the side cover and find the main fuse blew.

I hiked back home to look through my toolbox for a spare fuse only to remember I carry a case of spare fuse in my jacket. Hike back.

Pop in new fuse. Off I go, but 30 seconds later, FOMPF! It blows again. No problem. El foil aluminio.. I tear off a piece of foil and while I'm doing this, I distinctly recall thinking "shouldn't I be checking why the fuse keeps blowing?" at the same time I put in the fuse wrapped in foil and kick her up. Immediately a gnarly cloud of smoke comes out from under the gas tank.

Off come seat, off comes gas tank, and I find the wires leading to the ignition is a hot mess. It was laying right on top of the valve cover. PO didn't bother to secure it properly and it had popped out and fried itself sunny side up.

Then I hike back to get my truck so I could put my bike in there, look in the back of my truck and saw that I forgot to clean out the cow manure that was in there last week. $&%$ me. Too late. My bike is standing alone out there in the middle of nowhere.

Drive back, and decide to hotwire the ignition (see 2nd pic) so I could run the bike up the ramp and into the truck because nobody could come help immediately and I wasn't too keen on leaving the bike for there too long. So the bike jumps into into the truck and slips in the cow manure, taking me down with it.

Come back home, take bike out, clean the #&%! off it and park it. Still smells like a cow farted. I have to order another ignition, look at the time, and find out it's past 5 which means the cleaner is closed and I forgot to go there to pick up my dress shirt because I'm going out tonight. Now I have to remember where I put the iron if I still have it.

Forget it.. any day that ends with me taking a hot shower and finally sitting down and kicking back, is a good one.

Of course only now do I remember that I still forgot to clean out the cow manure. And I still have to go out tonight.

[Jayhawk]

I agree.

My question here is: do I need to drain all the oil again (just filled with brand new 10w-40 castrol) before I apply JB bond over the small crack I missed? It doesn't leak when engine is cold, but I know surface prep is everything, and I risk fouling the oil inside when using acetone, applying JB bond, etc. Or is that too small of a deal?

You don't need to drain the oil, but as you mentioned, you do need to scrub and texture the case surface around the crack before applying  JB Weld.
If don't already have a few, I suggest stopping by your local hardware store and buying a few "toothbrush-style" brass brushes; here's an example:



I like the three pack with one brass brush, one fiber, and one stainless.

[deafcaferacer]

I agree.

You don't need to drain the oil, but as you mentioned, you do need to scrub and texture the case surface around the crack before applying  JB Weld.
If don't already have a few, I suggest stopping by your local hardware store and buying a few "toothbrush-style" brass brushes; here's an example:

I like the three pack with one brass brush, one fiber, and one stainless.

Thanks, JH and Sean.

Going to the store today to get that. That will allow me to etch the surface without taking off the chain. I'll be applying  JB bond later today.. plenty of downtime as I have to wait for the new ignition.

I am also thinking about switching to the blade type fusebox rather than continue with the old setup because those types of fuses are getting harder to find. I remember seeing somewhere that Hondaman sells such a replacement setup, but can't find the link.

[Stev-o]

Sorry to say but using foil is a bad idea and I guess loading your bike in a truck of cow crap is too, but makes for a good story.
Here's the link....

http://sohc4shop.com/catalog/product_info.php?cPath=23&products_id=48

[cheftuskey121]

I'd lie if I said that story didn't give me a good chuckle. We've all had days like that though. Keep your head up

[deafcaferacer]

Sorry to say but using foil is a bad idea and I guess loading your bike in a truck of cow crap is too, but makes for a good story.
Here's the link....

http://sohc4shop.com/catalog/product_info.php?cPath=23&products_id=48

Why is using foil a bad idea? Couldn't I use it in a pinch? I wasn't intending to continually use it, just to get the bike home.

[deafcaferacer]

I'd lie if I said that story didn't give me a good chuckle. We've all had days like that though. Keep your head up

Thanks, I'm glad you enjoyed the story.. makes the whole thing worthwhile if it made someone laugh.

[iron_worker]

x2 for chuckling at your expense... 

Sorry man. If nothing else it gave other people a good laugh. ha

IW

[Stev-o]

Sorry to say but using foil is a bad idea and I guess loading your bike in a truck of cow crap is too, but makes for a good story.
Here's the link....

http://sohc4shop.com/catalog/product_info.php?cPath=23&products_id=48

Why is using foil a bad idea?

You risk burning up wiring.

[deafcaferacer]

New ignition arrived today. I plugged in, routing wires away from valve cover, took her out for a test ride, and the fuse blew about 5 mins into the ride. Tried to plug in a 20amp fuse just to get it home and that blew too.

Took everything apart and went over all the wiring. Nothing is exposed, no frays or worn wires, no loose connections. I am just completely puzzled.

[deafcaferacer]

Well, after reading through the archives, I did the short test by bridging the connection of the main fuse with a lightbulb (12v) and it went on, so there is a short somewhere.  Wondering how to begin to diagnose. What should I disconnect first?

[Elan]

Is the wiring all stock? sorry if you already mentioned that. Does it blow when switched on but engine not running?

I would...
 unplug the BR/W wire from the black wire in the headlight(turn signals, brake light, gauge lights) and  unplug the B/W at the coils, and horn and see.

That should narrow down your search a lot. If it blew still, i'd unplug the alternator. if its not blowing then, try the coils and start the bike.

[deafcaferacer]

Is the wiring all stock? sorry if you already mentioned that. Does it blow when switched on but engine not running?

I would...
 unplug the BR/W wire from the black wire in the headlight(turn signals, brake light, gauge lights) and  unplug the B/W at the coils, and horn and see.

That should narrow down your search a lot. If it blew still, i'd unplug the alternator. if its not blowing then, try the coils and start the bike.

Hi Elan,

Yes, harness is stock.

Fuse does not blow when on, only when running (I would say warmed up).

What I've done so far was disconnect the fuse holder, checked for pinched wires, polished the fuse holders (Hondaman's tip was to use a .22 caliber bore polisher, but since I live in the city that is not a viable option, so I went the poor man's route and used emery paper wrapped around a pencil).

Wiggled, unconnected stuff then connected them. Put in new fuse, and it seems to be holding but I am not entirely convinced. I'm going to go around the block 1000 times before I venture any further. That way I can just push the bike home (and meet or exceed my daily workout regiment) if it blows again.

Had to stop diagnosis because it started raining, yet again. 

[deafcaferacer]

Stopped raining so I took her out for a spin and all looks fine, but I am still leery. I still have no idea how the short problem got solved. Still a little jumpy.

Took her around the block 1,001 times and a little more, then hit the open road. Really hit the gas, did quick acceleration, deceleration, etc. all seems fine. I'm liking that 17/48 arrangement.. the power band seems to have moved slightly a bit, down to the 50-80mph range.

[deafcaferacer]

Oh God. There is only one thing better than the very first time your bike fires up and you take it for a spin is the time when that machine is finely tuned, and the growl between your legs is strong and smooth and humming, and the warm night breeze blows by you as you steer under stars you never saw before. If this keeps up I plan to propose to her soon.

[cheftuskey121]

preach brother

[Cam]

Love the bike! Glad to see I'm not the only one mixing parts from other K models 

Oh God. There is only one thing better than the very first time your bike fires up and you take it for a spin is the time when that machine is finely tuned, and the growl between your legs is strong and smooth and humming, and the warm night breeze blows by you as you steer under stars you never saw before. If this keeps up I plan to propose to her soon.

This was like poetry haha

[deafcaferacer]

Love the bike! Glad to see I'm not the only one mixing parts from other K models 

Yeah we are the red-headed stepchildren our mother introduces after she moves in with her new boyfriend.

[Stev-o]

Love the bike! Glad to see I'm not the only one mixing parts from other K models 

Yeah we are the red-headed stepchildren our mother introduces after she moves in with her new boyfriend.

No, that's the CB650!

[754]

Thinking about where you live.. Never run a taillight smaller than a750 K1.    Light if you ride occasionally in the fog.. Unless a smaller one throws a good amount of light...
 Scary to ride into a fog bank on an interstate and then realize. Your light is the size of a golf ball..