Author Topic: CB 750 Project 1 - Rides Well but a few tweaks needed (Read 114418 times)

Terry in Australia · « **Reply #500 on:** January 31, 2016, 06:47:50 PM »

I reckon you'd melt your engine cases long before you'd achieve a bond strong enough to remove the sheared bolt Cal, another fine theory, but in practise? Doubtful in the extreme......

calj737 · « **Reply #501 on:** January 31, 2016, 06:50:07 PM »

Not even close Terry. TIG to steel versus the heat to melt aluminum. You're not laying root passes and beads, your dropping a tack or two on the end of a bolt. Done it a few times quite successfully and without evidence ever of it to the case.

Terry in Australia · « **Reply #502 on:** January 31, 2016, 07:57:10 PM »

So let me get this right Cal, you snap a 6mm bolt when trying to undo it, and somehow by magic, one or two tiny tacks (1 or 2 mm in diameter?) will be strong enough to allow you to remove the jammed bolt? Unbelievable! You must be the world's greatest welder!

timbo750 · « **Reply #503 on:** February 01, 2016, 12:47:14 AM »

I have been sorting out some of the electrical bits. Got New plugs on the stator coil and color coded with heat shrink. Also rewired the plug and short harness that it plugs into. Now I am trying to decide what to do with the rectifier and regulator. I have stock units but they are pretty filthy and are showing some corrosion. I know everyone talks about how the old units are robust and reliable but I also like solid state electrics.

Edit: also, I know how to check if a solenoid works but how reliable are the starter relays in these bikes. Is it worth replacing for peace of mind?

Terry in Australia · « **Reply #504 on:** February 01, 2016, 01:28:28 AM »

I don't remember having any problems with starter solenoids Tim, but rec/regs are a different matter. I replaced the one on my K1 with a modern one and solved my charging woes. You don't need to spend a lot of money though, just about any modern rec/reg will work. Cheers, Terry.

timbo750 · « **Reply #505 on:** February 01, 2016, 01:32:00 AM »

Terry thanks. Z1 Enterprises has one for $99.50 and the 5ohm coils I need are $130, but I can get a rectifier from flea bay from Brisbane for $40 including delivery. From what you are saying I should save myself $60 buck plus postage.

Terry in Australia · « **Reply #506 on:** February 01, 2016, 02:29:15 AM »

That's good mate, Z1 Enterprises are cheap, and the owner, Jeff, is a member here, and a good bloke. He used to just sell Kawasaki stuff until an Aussie member convinced him to sell SOHC4 stuff.

I needed some bits for some Mikuni smooth bore carbs, so he stripped a set of his old carbs and sent me the parts for free, I couldn't recommend him more highly. Cheers, Terry.

timbo750 · « **Reply #507 on:** February 01, 2016, 02:43:50 AM »

I ordered the rectifier from ebay, couldn't justify twice the price for something that is essentially simple electronics. I have purchsed from Z1 parts before but Z1 enterprises seem to sell better stuff.

Terry in Australia · « **Reply #508 on:** February 01, 2016, 08:52:35 PM »

When you say "rectifier" Tim, do you mean "regulator/rectifier"? That's what you want, a modern regulator rectifier combined into one module, unlike the two separate units our bikes came with 45 years ago. Cheers, Terry.

timbo750 · « **Reply #509 on:** February 01, 2016, 09:00:57 PM »

Yes mate. Just being lazy and not typing the hole word. I could only find one with the same number of wires.

timbo750 · « **Reply #510 on:** February 05, 2016, 05:55:51 PM »

Got my new rectifier but the wiring needs to be sorted and I have no wiring diagram. I have posted question to group, here is the link if anyone can help.

http://forums.sohc4.net/index.php/topic,154985.new.html#new

Also I need to sort out my side stand. I have an old rusty unit that will clean up alright but when I test fitted it the bike leant over too much for my liking, I think it will cause fuel to leak out of the carby bowls. the other is a nice new chrome unit but it is too long, the bike is almost as vertical as the centre stand. Does anyone know what is an ideal length for a centre stand, this prices I have been looking at seem to high too me so I think I can get one made.

Terry in Australia · « **Reply #511 on:** February 06, 2016, 04:13:43 AM »

You're between a rock and hard place there mate, the sh1tty old thing on the left should be thrown in a bin, and the one on the right was meant for choppers with extended forks, hence why it's too long.

Interestingly though, I bought one exactly the same as the chrome one years ago and heated it up with my oxy torch and just bent it a bit, and it was fine until I found a good used OEM sidestand. I've probably still got it in my garage somewhere. Cheers, Terry.

timbo750 · « **Reply #512 on:** February 10, 2016, 02:00:18 AM »

Need some help working out were some of the wiring goes. The first is the neutral switch wire, at first I thought I ran up in between the alternator and gear selector cover but I can't seem to get a wire in there, but if it runs underneath then does it just a couple of cable ties to keep it up out of the way.

I was struggling to work out were the oil pressure wires goes but it would seem that passes past the starter motor, I first had the starter motor wire coming out were the pressure switch wire goes in, what a noob. I am also gathering that the points cable runs underneath somewhere but cant work that one out either.

while we are working out where things go I also need some indication of where the clutch cable goes, I have run it a few ways and most seem ok but nothing seems to be perfect but I must admit I am not likely to get it perfect due to the flat bars.

I got the oil apart as well and sent them off to the local hydraulic hose repairer and will get that back tomorrow, also got some stuff back from the electroplaters, got a new battery and all I need now is a clean oil tank (its getting the molasses treatment) my coils to show up, and the new regulator and rectifier. Things are starting to happen.

calj737 · « **Reply #513 on:** February 10, 2016, 03:58:11 AM »

Both the NEUTRAL and OIL wires come from under your left engine/side cover, hit the 8-way plug from your alternator harness, then they move through the electrical panel, then off to the front end where they terminate at the gauges. IF you look at the Solenoid, Reg and Rec plugs, you'll see them popping up here and there. But they originate under the left, and join the first plug to be captured into the harness from that point.

timbo750 · « **Reply #514 on:** February 10, 2016, 03:49:45 PM »

Cal thanks. I think I need to find some pictures or diagrams, the wiring on this bike was shambles and all over the place when I got it so I have nothing to go by here.

I also just picked up these.

Retro Rocket · « **Reply #515 on:** February 10, 2016, 03:53:26 PM »

Quote from: timbo750 on February 10, 2016, 03:49:45 PM

Cal thanks. I think I need to find some pictures or diagrams, the wiring on this bike was shambles and all over the place when I got it so I have nothing to go by here.

I also just picked up these.

Where did you get the oil lines Tim..?

timbo750 · « **Reply #516 on:** February 10, 2016, 04:20:15 PM »

I was lucky enough to have 2 sets. So I pulled one apart cleaned the fittings and went to our local Pirtek where we get our machinery hoses fixed. He had the hose which has a Teflon inner and ordered in special crimps because of the Aluminum fittings so they wouldn't get crushed. I gave him my second set to use as a template for the length.

Terry in Australia · « **Reply #517 on:** February 10, 2016, 04:51:19 PM »

Well done with those hoses Tim, I went to ENZED here in Canberra and they wouldn't crimp new hose onto my old fittings, so I just bought a couple of metres of their plain black rubber high pressure oil hose for $26, which I thought was very fair, and will do to get Mikes bike finished and out of my garage. ; D

mystic_1 · « **Reply #518 on:** February 10, 2016, 04:51:40 PM »

Those lines look great, should be bulletproof.

Looks like uncoated stainless braid, watch out for chafing where they ride against the case, frame,and swingarm, that'll eat through your paint right quick if you let it.

mystic_1

timbo750 · « **Reply #519 on:** February 10, 2016, 05:16:05 PM »

Mystic, thanks for that I will work out some unobtrusive way to prtect the frame.

Terry the hoses weren't cheap but they should be bulletproof as mystic said. Cost $130 each and I would not of got them if I couldn't claim them through work.

calj737 · « **Reply #520 on:** February 10, 2016, 09:17:37 PM »

Quote from: timbo750 on February 10, 2016, 03:49:45 PM

I think I need to find some pictures or diagrams, the wiring on this bike was shambles and all over the place when I got it so I have nothing to go by here.

couldn't determine whether yours is a K1, 2, 3-7 or what. But heres a K1 colored diagram:
http://www.cmsnl.com/classic-honda-fansite/honda_wiring_diagrams/CB750(K2).jpg

Bottom of the page, center, locate the OIL switch. BLU/RED wire from it passes with the harness from the STATOR (those thick black "bars" are physical plastic connectors on your bike). Then through a bullet connector in the harness to the gauge light.

Start again, look further to the right and locate the NEUTRAL switch. GRN/RED wire the other side of the AC Generator. See it is gathered into an 8-way plug, 7 wires. Then through another bullet connector, and on to the gauge. Pretty simple really. The physical switch (NEUTRAL) is under the bike, and comes up behind the shift cover, to the right of the sprocket and gathers with the OIL and STATOR wires until it hits the 8-way plug. Go to the connected side of the plug, and locate the OIL and the NEUTRAL wire exiting the plug, and trace them to the gauge.

You've built a bike, man this is the easy stuff!

timbo750 · « **Reply #521 on:** February 10, 2016, 11:19:16 PM »

Just got these as well, could be a busy weekend coming up. The oil tank is in a molasses bath.

Terry in Australia · « **Reply #522 on:** February 11, 2016, 03:13:39 AM »

Good work Tim, and I'm glad I didn't go to Pirtek, that price seems a little high, but I'm sure they're worth it. I'll just have to slum it with my 5 dollar ENZED hoses......

timbo750 · « **Reply #523 on:** February 11, 2016, 12:13:06 PM »

I had a look at Yamiya and mine are still cheaper. Their SS braided only hane a hose clamp with shiny cover.

Terry in Australia · « **Reply #524 on:** February 11, 2016, 02:29:12 PM »

Yeah, the Carpy ones were el cheap I braided hose with shiny covers over hose clamps, I'll use them with the black ENZED hose just because they look pretty.

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Author Topic: CB 750 Project 1 - Rides Well but a few tweaks needed (Read 114418 times)