Project Alan's CB250 Nighthawk

Thanks man, I wasn't sure if the early CB750K fender was going to be overkill with the ally tail or not but it sure is leaner and more inline with the rest of the seat and tank.

 

Thanks GI, lots of differences between forums if one gets around enough.
I appreciate your assistance.

 

Thanks Minimac, I hope to have a other update later this week.

 

Thanks Gents, sorry this build got stalled out. Work was busy, then the pandemic, furlough, more pandemic, a job change, more pandemic, and these days I've got plenty of time but no motivation.

Last spring during lockdown I'd picked up a 1978 CB750K basketcase that took up most of the summer and has been monopolizing my thoughts.

I'm hoping to get back to this 250, pretty much it just needs reassembly and a few parts. I'm debating whether or not I should get it on the road legally early in the season, and then tear it down for paint when temps warm up enough.

I'll try to update this thread a little more often.

 

Just reread and wanted to say that I don't want to imply there's been any let up on the covid front. And then there's the American political landscape...

Not sure how any of this weighs in with you all but I'll bet you're all ready for summer and a great riding season after some months at home.

I'm hoping to put some miles on myself this year, 250 or not.

 

Wow, long time between updates. We've survived Covid free, been furloughed and back to work, changed jobs, my gf closed her Salon and then some moron bought the building we'd been renting in for 10 years...so new apartment, no workshop, everything in storage...

This afternoon I dug the 250s frame out of storage, found my swingarm seals & steering bearing seals, front & rear wheels, forks.... But not the paint I bought this summer back before every spray-paint aisle went bare.

I've got the frame and stuff here at the apartment so I can work on it whenever. I've got some disassembly and cleaning to do, some parts will be flat black, some gloss black, and some Stainless Gray if I can find it. I'd love to make it a roller before the warm weather is gone, I'm not afraid to leave it under a cover all fall and winter to work on it whenever I can.

I'm hoping for the best.

 

Ah. 69 degrees and 53% humidity. I found the Rustoleum 7887830 Stainless Steel Appliance epoxy paint that I picked up this summer and started at about 1pm with just brake cleaner and paper towels followed by 150 dry paper and a liberal application of brake cleaner. I only had 2 "oops moments" forgot to mask the vin tag but caught it before I sprayed over it, and the top triple that I'd sprayed Stainless was supposed to be flat black, both easily remedied.

 

Before


After

 

Steering stops are in, they're about 1.5" high and should do fine, too dark and damp to put it back together tonight. I used 5/16-24 grade 8 bolts, 2" long. The triple drilled so easily, and tapped easily too. One side is perfect but the other slants out about .060" (1.5mm)

 

Tuesday's update. Sheltered from direct rainfall I was able to pack the tapered rollers with grease and install the triples for the last time. I test fitted my steering stop bolts without their nuts and the bolt heads contacted the frame stops, back on went the nuts and a little red loctite. The shafts of the bolts contact the frame stops, and there's plenty of room between the fork tubes and tank at full lock on both sides.

The front wheel was less fun. Turns out I'd grabbed the wrong speedometer drive (this one's for an 18" wheel) and the wrong spacer too (too narrow) so I'll have to make a trip back to storage. But it's on there for photos anyhow.
The rear end of the frame is sitting on the ground, so don't mind the fork angle.

I'll have to find a block of wood to set the frame on, or hang it from a tiedown strap (more likely) to get that rear wheel on. Still no sign of a kickstand at storage.

 

Thanks Murdo!

Looking at those 2 wide photos I've been thinking of the nearly 140mm of fork travel and how those gaitors are likely a limiting factor. Admittedly the bottoms of those gaitors aren't in place yet, stretched over the tops of the fork lowers, so that'll decompress them a bit.

And these forks are from a bike 90kg heavier. Built with stock springs, stock (LONG) preload spacer, 3rd hole in the damper rods, and a set of cheap cartridge emulators, filled with cheap ATF (since I figured I'd be back in there to adjust the emulators). I guess I'll know when I ride it, I'm about 118kg so maybe it'll all be fine.

 

Ok, Friday's update.
I was able to do a little assembly this afternoon. This is a CB750 headlight with some fork ears I made in 2008, all painted the same color as the wheels. I bolted on the rear wheel and connected the linkage and brake stay. I bolted on the right foot peg, but the left I'd found turned out to be from a different bike. I added the washers and nuts to the upper shock mounts, stretched the bottoms of the gaiters over the tops of the fork lowers and set the front fender in place, it's going to take a little work to make it fit.

 

Tuesday, an update but little progress. I installed the EBay fuel cap and sat the tank and seat on the frame. Fork ears are 3/8" from the tank at full lock on both sides. I sat on the bike for a few minutes and it's tall. I'll flat foot it in boots but in sneakers it's a little tall. It's likely Im going to have to do something about the stock footpeg position, it's just too far forward.

 

Still unable to locate the box of parts for this bike, today I hauled a partsbike home from storage to swap over the wiring, airbox, kickstand and probably a few other things I can't think of.





At least I'll be able to get right to work when time avails itself.

 

This afternoon I went out and spent some time with this bike before I ran out of daylight. I swapped over the handlebar switches, throttle tube and throttle cables. I moved the battery box and air box, and the wiring harness. Also the rear brake switch and spring.

*** I'm having a little trouble wrapping my head around the way the switch's spring is supposed to attach to the brake rod pivot. When the pivot turns and the rear brake is actuated, the spring doesn't pull the brake switch plunger and the geometry is way off. I was running out of daylight and gave up, I wonder if maybe I grabbed the 750Nighthawk brake pivot & rod that came with the forks by accident?
I'll have to try swapping them to see if there's any improvement.

No pictures today sorry.

 

As it turns out I did grab the brake pivot and actuator rod from the 750.



Today I added the cheapest Chineseium LED turn signals I could find, I think I got 4 of these and an appropriate flasher shipped for ~$7 from eBay in early 2017.

These predate the current offering that strobe like a late model Mustang rear signal, these aren't bendy either, but they look better than I'd hoped.

 

Cool, I was wondering if they'd be bright enough for daytime use.