Author Topic: my "crashed doing 80 and somehow lived" k4 750 rebuild (Read 8380 times)

mrbreeze · « **Reply #25 on:** August 04, 2016, 12:42:23 PM »

Seems like you like to haul a$$ (speeds of 80-105 mph mentioned) so that's all the more reason for you to have good tires, suspension, and quality gear. Have fun man but be very careful. There are too many meathead cagers out there that will ruin your day!!

SOHC4 Cafe Racer Fan · « **Reply #26 on:** August 04, 2016, 02:43:28 PM »

105 mph on those tires!? I hope not and I hope not in traffic even with good tires, brakes and suspension.

nobody · « **Reply #27 on:** August 12, 2016, 08:50:34 AM »

They're Metzler ME880 H rated, they're supposed to be good up to about 140, this bike runs dry around 118 so I think I'm good. But yes, I do like to go fast, I GOES HARD! Not around traffic or houses though, mostly on highway runs or mountain touges. I mean, in it's time this bike was the fastest bike on the planet, I didn't buy the fastest bike on the planet to go slow.

A few developments over the last week but not enough spent on the bike so not as much progress as planned. SLACKIN!

Cut some grooves in the front brakes, supposedly helps with brake squeak

Switched my 105 jets for 115s, gotta remember to do a plug chop later to see if I need to go higher or lower.

Got some new shoes on my Fairlady

Gonna finish assembling the front end and reinstall the carbs and airbox this weekend. I think I figured out what might be causing that rear brake clunk too, found a spacer that I think might belong up in there somewhere.

nobody · « **Reply #28 on:** August 15, 2016, 09:43:38 AM »

Got her off the jack stands this weekend and down onto her own two feet, rolled it around and made vroom vroom noises like a 10 year old. I also put that spacer back in the rear brakes and the *clunk* noise went away, didn't get the carbs and airbox in there but that's up next.

70CB750 · « **Reply #29 on:** August 15, 2016, 02:26:03 PM »

Everybody makes vroom, vroom noises, right?

SOHC4 Cafe Racer Fan · « **Reply #30 on:** August 15, 2016, 02:38:52 PM »

Quote from: 70CB750 on August 15, 2016, 02:26:03 PM

Everybody makes vroom, vroom noises, right?

Maybe not always audibly, but hells yes.

nobody · « **Reply #31 on:** August 16, 2016, 10:58:25 AM »

Haha, running on that high octane Folgers huh?

I saw a kid in the neighborhood with bicycle cards pinned to his spokes, I was inspired.

nobody · « **Reply #32 on:** October 12, 2016, 09:46:41 AM »

Just in time for the snow, I'm finally getting everything back together.

I mounted the carbs and airbox, with some holes drilled...

and a fabricated scoop per HondaMan recommendations.

I still need to source longer exhaust bolts, or maybe studs, before the pipes can go on.

I mounted the taillights...

Still have to sort out a few wire splitters so I can run two bulbs versus the factory single bulb.

I also mounted my Norman Hyde M bars with all the controls, nice alternative to clubmans

Next step is to break out the wiring diagram and figure out this rats' nest of wires

Don R · « **Reply #33 on:** October 13, 2016, 08:08:30 PM »

I recently pulled a set of forks apart that had 8mm seals and had washers above them and under the circlip. That is the only one I've seen like that. Some seals seem to have the spacer molded in, are 11mm. Most I have taken out or put in are like yours.

josherr · « **Reply #34 on:** October 13, 2016, 08:21:31 PM »

Where did you get that tail light ?
Plan on running something like that on my 750

Sent from my iPhone using Tapatalk

nobody · « **Reply #35 on:** October 14, 2016, 09:43:43 AM »

http://www.speedmotoco.com/

They have some pretty cool stuff, located in Portland, Oregon. Half of the time they're either working on the shop race bike or out at the vintage races.

nobody · « **Reply #36 on:** October 23, 2016, 11:05:45 AM »

Some progress updates from yesterday:

Got a new Hondaman fuse box, fits perfectly.

Wired up the taillights, nice and bright.

Mounted my exhaust with some ACE bolts
(8.8 strength, 8mm 1.25 pitch 35mm long)

And here it was just as I left it last night at 11pm

I was able to start it up for the first time since this thread began! I love this exhaust, loud, mean and smooth. Though it's only running on 3 cylinders at the moment, so it seems I have some troubleshooting to do.

nobody · « **Reply #37 on:** October 23, 2016, 04:33:48 PM »

All four plugs were fouled and gassy, so I cleaned them up and switched jets from 115 to 110.

Still firing on only 3 cylinders, I'm beginning to suspect the coils or wires maybe. Sigh...

seanbarney41 · « **Reply #38 on:** October 23, 2016, 06:03:58 PM »

Pull your idle jets and blow them out...

Pull the idle jet for the cylinder that isn't firing, they can get plugged by a drop of water

nobody · « **Reply #39 on:** October 23, 2016, 09:39:13 PM »

I pulled all plugs again, fuel smell on the dead one so I think the carbs are okay. I decided to switch the plug on the dead cylinder with another cylinder, the dead cylinder moved with the plug. So I re-cleaned the hell out of the plugs, sanded the gap leads, then reinstalled.

Tada!!! Sparking across all four and running clean. Ran it around the neighborhood on a couple test rides, adjusting the brakes and clutch, as well as the idle. I wouldn't call it done yet but at the moment IT'S ALIIIIIIIIIIIIIIVE!

This list looked a lot more organized at the start, but much more satisfying right now.

nobody · « **Reply #40 on:** October 24, 2016, 08:56:12 AM »

Still got a few things left to do, mostly things to buy...

Coils, wires, new plugs. I have some NGK Iridium plugs but I've now read I shouldn't use them. Some blinkers maybe, something LED and super minimal. I found some tiny LED blinkers some time back but lost the link so I'll have to look around. I have another front fender, I've made mounts to run it over the rear, double fender 750 may still happen down the road.

and a brat style seat, still uses the stock hinges
http://www.motorcycleseatsdirect.com/1972-1976-honda-cb750-k2-k3-k4-k5-k6-motorcycle-complete-cafe-racer-seat-cx500-style-new/

nobody · « **Reply #41 on:** October 26, 2016, 10:13:19 AM »

Spent some time tinkering last night.

Mounted up a hanger for my exhaust, get some weight off those front bolts.

Decided to install the chain guard to avoid it eating my girlfriend's pants.

Rode it about 3 miles last night, ran smooth and strong, straight and even. I figured I'd be more nervous back on a bike after my spill but I feel pretty comfortable out there. I definitely have wobbly legs, and am not riding like a racer just yet but I can already see myself getting there.

Happy to be back on two wheels, it reminds me that feeling you got as a kid on your bike, riding around the world.

Free as a bird

markreimer · « **Reply #42 on:** October 26, 2016, 10:39:26 AM »

looks good! Congrats on being back on the road! also that's a nice looking exhaust, is it a Cycle-X?

SOHC4 Cafe Racer Fan · « **Reply #43 on:** October 26, 2016, 11:18:40 AM »

Thumbs up on getting back up on the horse.

nobody · « **Reply #44 on:** October 26, 2016, 12:24:22 PM »

Quote from: markreimer on October 26, 2016, 10:39:26 AM

looks good! Congrats on being back on the road! also that's a nice looking exhaust, is it a Cycle-X?

Yeah, it's their Super 4 into 1. It has a super nice fit, real easy to hook up. Sounds sooooooo good, but super loud. Doesn't interfere with center stand usage, and you can leave it on for oil changes as there's room for the filter and room under the plug.

$379.00 Part number: EX-4into1-SUPER-BLK

SOHC4 Cafe Racer Fan · « **Reply #45 on:** October 26, 2016, 03:29:21 PM »

The price is very good. I assume that the tubes are high-temp painted mild steel.

Stev-o · « **Reply #46 on:** October 26, 2016, 04:00:53 PM »

Good to hear you are back!

nobody · « **Reply #47 on:** October 28, 2016, 11:16:56 AM »

Went to the gas station last night and noticed my chain was cutting down part of my center stand.

This doesn't seem right

I swapped a bracket from the old 4-2 exhaust. Problem solved.

Seem to keep finding stuff I need to fix or adjust

Stev-o · « **Reply #48 on:** October 29, 2016, 03:40:59 PM »

That's a common issue when stock exhaust is removed.

nobody · « **Reply #49 on:** October 31, 2016, 10:34:02 AM »

Broke my clutch cable on the way to work this morning. Got lucky that I was down the road from an auto shop and even luckier that they were having some transmissions delivered by a guy with a box truck and a lift gate. So for $30 he loaded my bike up and got me back home.

Since I didn't take any pictures of the bike in the truck and we all like pictures, here's another classic driveway picture from this weekend.

News:

Author Topic: my "crashed doing 80 and somehow lived" k4 750 rebuild (Read 8380 times)