Author Topic: 1975 CB750 K5 "Rhonda the Honda" (Read 90405 times)

SOHC4 Cafe Racer Fan · « **Reply #275 on:** February 18, 2017, 08:27:54 am »

"Yeah!!"

Hey, what's going on with your taillight flickering?

evanphi · « **Reply #276 on:** February 18, 2017, 08:42:25 am »

Don't know. I had all the running lights off. The headlight/tach light wasn't flickering.

When the headlight switch is ON it doesn't flicker off.

RAFster122s · « **Reply #277 on:** February 19, 2017, 02:47:38 am »

Typically that would be a bad ground path somewhere and the voltage from the circuit in question is finding path to ground through another circuit. Volvo 240s would do this if the grounds needed cleaning...get all kinds of strange behavior when the voltage would return through another component not turned on... Seat belt warning lamp would light or fan or some other strange behavior of another circuit.
Suggest you check your tail lamp's ground and the other grounds on the bike... motor ground as well to the frame. Headlight bucket, battery ground, etc. Never hurts to clean them up while it is off the road...doing it while on the side of the road is definitely no fun.

evanphi · « **Reply #278 on:** February 19, 2017, 04:33:51 pm »

Hm. I will have to check the tail light out. I suspect it is only the tail light because no other lights are flashing ON when the switch is set to off, as was the case that night. Usually the switch is ON so all running lights are on as well as the headlight, so I wouldn't notice it.

Stev-o · « **Reply #279 on:** February 21, 2017, 05:01:17 pm »

Was that a cold engine start? My K4 wont start if given throttle like that with full choke.

Bike sounds great!

evanphi · « **Reply #280 on:** February 21, 2017, 05:36:19 pm »

Quote from: Stev-o on February 21, 2017, 05:01:17 pm

Was that a cold engine start? My K4 wont start if given throttle like that with full choke.

Bike sounds great!

Yep very cold. It was -5C outside. I had been working in there for about 2 hours with a small heater and the halogen lights on, though, to warm up the oil a bit.

evanphi · « **Reply #281 on:** February 25, 2017, 07:21:57 pm »

OK so shop night was tonight.

First thing's first, put the LED lights into the tach. They don't seem a whole lot brighter. Oh well.
Next up, cut and routed the new 3.5mm drain hoses for the carbs. Hopefully they stay nice and rubbery for a long time. They all sit about 1.5" below the center stand axle.

That was all I needed to do tonight. But I also wanted to see why that tail light was flickering last week.

Took it off and disassembled it, then remounted. Nothing out of the ordinary.
Then I removed the rear brake switch and routed the wiring through the hole in the rear engine mount just ahead of the oil tank drain bolt. Seems like a smart place to run it. When I turned on the bike the rear brake switch was activated, so I had do dial it down. I think this may have been why it was blinking previously.

Started the bike up again to hear it roar. No more blinking brake light. Could have been the switch, ~~or could have been the mounting screws for the light, which is how it grounds, being dirty.~~ On second thought it was the switch. The lights were all turned off when I did that video. The switch was just too tight and was vibrating on.

Not wanting to waste any more time, I mounted the Delkevic muffler bracket/stand stopper to the right passenger peg bolt. Had to open up the hole slightly to fit the M12 bolt that holds the peg on. Will have to further elongate this hole so the bracket sits a bit lower. The center stand foot on the left side of the bike seems awfully close to the chain.

Last up to fabricate is an exhaust reducer pipe for the collector to the muffler. The reducer pipe needs to be 16GA stainless steel reducing from 2.5"ID to 2.25"OD. Looks like best option is going to a muffler shop for this. 2.25" OD stainless 16GA exhaust pipe, and then have the end expanded with a hydraulic expander to 2.5" ID.

The steering damper bracket/speedometer bracket should arrive Wednesday, and I also ordered the Magna 5OHM coil and wire set from 4into1. That should arrive soon too.

Seeing more and more bikes out on the road as our mega snowfall keeps melting...

evanphi · « **Reply #282 on:** February 27, 2017, 11:13:26 am »

clamp arrived today. Put the speedo right where I wanted it.

Variantbuilder · « **Reply #283 on:** February 27, 2017, 09:35:28 pm »

for the 4into1 exhaust, did you use a certain size jet? and how did you tune it?

evanphi · « **Reply #284 on:** February 28, 2017, 04:55:46 am »

Plug chops. I had my mixture screws almost completely closed last year just to get it to kick start, so I bumped up to 42s for this year, set to 1 turn out as of now.

evanphi · « **Reply #285 on:** March 05, 2017, 10:01:39 am »

Installed the Magna coils.

evanphi · « **Reply #286 on:** March 09, 2017, 07:46:38 am »

Ordered a length of exhaust tubing to make my reducer pipe! 90$ CAD for a 4 foot piece... I guess I'll have to make something else out of stainless now, too.

http://www.tdotperformance.ca/flowmaster-mb121448-straight-tube-2-25-in-o-d-48-in-length-stainless-steel.html

evanphi · « **Reply #287 on:** April 03, 2017, 06:41:47 am »

Alright suckers, I'm back. Two week hiatus for the birth of our son.

Finished up Rhonda for this year by mounting the muffler to the collector.

So it turns out that the piece of stainless exhaust pipe I bought was 409 stainless and prone to rusting anyway. So if anyone wants to buy it I'll give it for a good price.

Onto Plan B, which eliminates a clamp anyway.

Had my dad turn down a piece of stainless pipe from his boat parts bin. Fit inside the collector and then made a bit of a venturi into it. Then the cone slips onto this. Welds aren't perfect, and I cleaned up and polished what I could. I'll likely do some more polishing before long. If funds allow I may purchase another slip-on cone to fit right over the collector. Maybe next year. The fit is very tight from the cone to the bung, so I used some Nickel anti-seize (rated to 2500F) on that joint to aid in removal later on.

Fire the bike up and it sounds nice and mean still, just with a softer edge.

And if my exhaust tuning theory is correct, then a alight restriction means better bottom end, but the nice open collector will give more top end. Who knows. I'm not exactly concerned.

calj737 · « **Reply #288 on:** April 03, 2017, 06:59:46 am »

Quote from: evanphi on April 03, 2017, 06:41:47 am

Had my dad turn down a piece of stainless pipe from his boat parts bin. Welds aren't perfect, and I cleaned up and polished what I could.

Did he MIG that weld? If so, if he used ER70s2 that weld will rust. Gotta use Stainless wire (TIG or MIG) to prevent it.

evanphi · « **Reply #289 on:** April 03, 2017, 08:31:15 am »

Quote from: calj737 on April 03, 2017, 06:59:46 am

Quote from: evanphi on April 03, 2017, 06:41:47 am
Had my dad turn down a piece of stainless pipe from his boat parts bin. Welds aren't perfect, and I cleaned up and polished what I could.
Did he MIG that weld? If so, if he used ER70s2 that weld will rust. Gotta use Stainless wire (TIG or MIG) to prevent it.

TIG

calj737 · « **Reply #290 on:** April 03, 2017, 08:36:24 am »

stainless or steel wire?

evanphi · « **Reply #291 on:** April 03, 2017, 09:17:44 am »

stainless

BPellerine · « **Reply #292 on:** April 06, 2017, 06:23:42 pm »

pipe looks good the way it is mounted!still cool in the east for riding yet!bill

evanphi · « **Reply #293 on:** April 07, 2017, 06:38:56 am »

Yep just getting into warmer weather now. Might try a shakedown this coming week, then hopefully start taking it to work next friday.

WesTenRacing · « **Reply #294 on:** April 07, 2017, 08:36:38 pm »

Quote from: evanphi on April 03, 2017, 06:41:47 am

Alright suckers, I'm back. Two week hiatus for the birth of our son.

Congrats on the addition!

Hope everyone's doing well.
Someone to help you in the garage!!

evanphi · « **Reply #295 on:** April 10, 2017, 08:35:15 am »

Rhonda's first day in the sun since November! Took her for a nice shakedown run. Carb 1 was overflowing, but quickly remedied by removing bowl and replacing again. I'll be removing the stock mirrors and switch back to my bar-end mirror. They're just too tall and take away from the look I'm going for. Hand guards will come off shortly as the weather warms up. AAAAND I need to take apart the Tach and replace the damping oil. Or maybe just a shot of lube is necessary. My tach is just bouncing all over the place, especially above 3K. But DAMN does she look good.

evanphi · « **Reply #296 on:** April 15, 2017, 05:03:27 pm »

Rhonda's updated Glam shot for 2017. The hand guards will go once things warm up a bit more.

Dang she's pretty!

Stev-o · « **Reply #297 on:** April 15, 2017, 07:26:12 pm »

Nice job on the exhaust. You happy with it?

evanphi · « **Reply #298 on:** April 17, 2017, 06:44:19 am »

Quote from: Stev-o on April 15, 2017, 07:26:12 pm

Nice job on the exhaust. You happy with it?

Very happy. If funds were available, I would have bought a 2.5" ID new cone, but... not this year. Maybe next year's bike budget will allow!

evanphi · « **Reply #299 on:** May 04, 2017, 06:36:48 pm »

So my taco does this:

I would like it to NOT do that so I have some 50,000Wt silicone RC diff oil on order. In the meantime I thought I would disassemble the tach to familiarize myself.

Repro. Yay. Here's what's inside:

That 5mm nut can unscrew and that bushing comes out. It is adjustable, it seems. The slotted section + locknut. Two tiny holes, also. These were barely visible when assembled.

So my question is: WTF do I do with all this?! It feels like there was what was left of some slick oil in that little chamber when I took it apart. Makes sense that this would be the damper pot? Just refill, reassemble, and be on my way then?

Other thoughts?

News:

Author Topic: 1975 CB750 K5 "Rhonda the Honda" (Read 90405 times)