Topic: Maduncle has FINALLY got himself a CB750K

[maduncle]

Well done Cliff, but I do remember telling you to check the tank for leaks before you had it painted, the tank has already been lined, so you've got a problem, sadly. If you can get the old POR15 stripped out without damaging your paint job well and good, but if not, start looking for another tank. Anyway, good to know that it goes. Cheers, Terry.

Yeah - and I told the guy who painted it to check for leaks before going all out on finish as part of the job.

The leak is from the underside of the tank, I am taking it to a good local welder who may be able to braise it up, the painter is prepared to repaint the tank at his cost once it is repaired.

I am after another CB750 tank anyway as I want a stock K2 green tank and side covers for the bike later on.

[Terry in Australia]

No worries, I tried soldering that tank because even though it was dent free, it was pretty badly corroded in the bottom. I think that brazing might be too much for it, unless he's going to braze a plate on underneath. The problem is the POR-15 liner, it'll need to be chemically removed before he can braze it, then re-applied once it's been repaired, so I doubt if your paint job will survive. Cheers, Terry.    

[calj737]

Even welding or brazing your tank with POR inside is a very bad idea. It is likely to ignite the liner and not stop. Even if you don't catch the liner on fire, you will melt away the liner from that area, and create an edge on open metal/liner that will be susceptible to infiltration later.

The easiest fix Cliff is to add a second layer (only a half portion) and focus on the areas of the tank where the pinholes are. Its safest and simplest and will normally solve an error in coverage from the first effort.

[maduncle]

Even welding or brazing your tank with POR inside is a very bad idea. It is likely to ignite the liner and not stop. Even if you don't catch the liner on fire, you will melt away the liner from that area, and create an edge on open metal/liner that will be susceptible to infiltration later.

The easiest fix Cliff is to add a second layer (only a half portion) and focus on the areas of the tank where the pinholes are. Its safest and simplest and will normally solve an error in coverage from the first effort.

Thanks for that - I will get a liner kit and do just that.

[Terry in Australia]

I know that you're hoping for an easy fix Cliff, but POR-15 doesn't stick well to POR-15 that's had fuel on it. I had that problem previously, I tried Cal's method, and the second layer didn't adhere to the old layer properly, and I had silvery slop in my float bowls, so I ditched that tank and lined another one, and had no further issues. It might work, but the kit is well over 100 bucks here, so you'd be better off using another tank. Cheers, Terry.

[maduncle]

I spoke with the guy here in Australia who sells the KBS tank liner kits. He recommended I buy the $27 small tin of liner, strip back the leaking area on the outside of the tank, apply one coat of liner with a brush, press a layer of fibreglass mat into the wet liner, then apply a second coat of liner over the top.

All done to the underside of the tank where it wont be seen, so for $27 I will try it and see if it fixes the pin hole for now.

Meanwhile I have another tank to get painted to replace this one and this one I plan to get painted in Honda Candy Bacchus Olive with K2 stripes - all nice and stock.

I also want to buy a pair of repro side covers to get painted at the same time and repro side cover badges - but the range of options on the 4 into 1 site confuses me - and I don't want to end up wit the wrong badges for the side covers.

Can anyone point me in the direction of repro side covers with the right badges?

[Terry in Australia]

I've probably got a pair here that you can have Cliff, freebies. Only problem is I'm in Adelaide until Friday, and my brother (in Townsville) died this morning, so I may have to fly up there on the weekend? Any K1-K6 sidecovers will fit, the badges on yours should be the early 750 Four script, and the diamonds are an amber colour, not red. (K1 only) Cheers, Terry.

[maduncle]

Very sorry to hear about your brother Terry.

No hurry - talk to you in a couple of weeks.

[SOHC4 Cafe Racer Fan]

I've probably got a pair here that you can have Cliff, freebies. Only problem is I'm in Adelaide until Friday, and my brother (in Townsville) died this morning, so I may have to fly up there on the weekend? Any K1-K6 sidecovers will fit, the badges on yours should be the early 750 Four script, and the diamonds are an amber colour, not red. (K1 only) Cheers, Terry.

So sorry for your loss, Terry.

[maduncle]

Got paid this week so I splashed some cash on 4 into 1 and got the side cover badges, and another fuel cap, latch and petcock.

Had to go via eBay to get the tank stripes as they were out of stock on 4 into 1.

All this should help put a nice semi stock look on the bike.

[maduncle]

Close now ...

My mechanic friend who has the bike has found that the oil pump was not pumping. When he pulled the pump an inspected it he found one of the plunger valves was stuck closed and not letting oil out (?).

So I sat down today and cut him a new oil pump gasket from gasket paper.

And thanks for that schematic too Terry, we will be checking for part number 2 in the lower case to make sure it is there.

[Terry in Australia]

No worries Cliff, the gasket set I gave you comes with an oil pump gasket, but anyway, cutting one from gasket paper should be fine. Make sure that the three O rings are in place as well, or once again, you won't have any oil pressure. Cheers, Terry.

[maduncle]

No worries Cliff, the gasket set I gave you comes with an oil pump gasket, but anyway, cutting one from gasket paper should be fine. Make sure that the three O rings are in place as well, or once again, you won't have any oil pressure. Cheers, Terry.

Thanks Terry - I will be checking for all those O rings during assembly for sure.

[maduncle]

This makes me happy.

Straight to 70 on start up.

All good for the Roadworthy Inspection now - although the brand new neutral light switch now does not work. It will pass anyway (its who you know ...)

Then a club permit and then on the road - should be out there within a week (fingers crossed).

[Terry in Australia]

Well done Cliff, you don't need a neutral light for a roadworthy anyway, so you'll be fine. That's a good quality oil pressure gauge too, there are crooked sellers out there that flog cheap chinese air compressor gauges as oil pressure gauges, and the needles fly off first time out. Cheers, Terry.  

[maduncle]

Okay...

So why does the petcock rub up against the carbie throttle linkage and stop the throttle opening fully?

Is it a wrong tank/carbie model combination of parts?

Pretty sure the carries are fitted correctly - all the boots went on in order and lined up.

Not sure what to do to get a few millimetres more space between the back of the petcock and the carbies ...

[Terry in Australia]

That' a good question Cliff, the tank (I presume it's the one I gave you) is from a K2, it's a K2 frame, the carbs are K2, so I've got absolutely no idea why you'd have that problem. There is a little bit of slop in the standard engine mounts so the engine can be tilted back or forwards a little, but not to the point where the tank would stop the carb linkages for rotating fully.

Not having a close up pic to look at, I have no choice but to ask some dumb questions. Are you using the original carb mounting rubbers, front and rear? The carb mounting rubbers are numbered 1-4, 1 being on the left (alternator) side, and 4 being on the ignition side. In that order, the numbers will be on top of the rubbers, with the numbers closest to the cylinder head, not the carbs. If you're using the OEM airbox, the rubber snorkels should be rotated so that the airbox's two 6mm mounting screws are an easy fit, ensuring that everything is lining up properly.

With the carbs and airbox correctly mounted, and the tank rubbers in place, nothing should affect the rotation of the carb linkages. It's probably a good idea to go back and double check your work, and if you still can't nut it out, post a pic or two so we can see the problem, and not have to hypothesize. Cheers, Terry.  

[maduncle]

Thanks Terry,

Checked all the rubbers - the new carb mount rubbers are on in the 1 to 4 order with the numbers facing up from alternator to ignition. The airbox screws were an easy fit, i fitted the airbox snorkels to the carbs on the correct angle to line up wit the airbag inlets then bolted the airbox in place. It is only a matter of a couple of a "poofteenth of an inch" clearance needed. Going to try shaving a bit off the back edge of the front tank mount rubbers to get the tank to move forward slightly (found that idea searching the forum here).

Wont be a big thing - just need to carefully check everything like you say.

[BPellerine]

another dumb question ,correct petcock?bill

[Terry in Australia]

Yes it is Bill. Cheers, Terry.

[maduncle]

Bit of a nudge, bit of a jiggle and all is good.

Close - but good.

Roadworthy next - then we ride!

[Terry in Australia]

If you get it registered before next weekend I'll be up for a ride with you Cliff!

[maduncle]

Update time.

Well, got the RWC and got the club permit done for the bike.

But then the starter motor clutch went and threw a hissy fit, so it took a wee while to get that sorted.

As of this evening - I need a stator cover gasket and a gear change cover gasket to replace the two new ones damaged when fixing the dodgy starter motor clutch assembly, then I am on the road.

Hopefully I can find those gaskets in the next day or two so I can ride this bike next weekend.

Then I can get stuck into the CB450K1 I bought last week...

[Terry in Australia]

Well done Cliff, I'm going to take Mike's Café Racer for it's first ever "test ride" next Saturday, maybe I'll see you on the road. Cheers, Terry.

[maduncle]

Update time.

Well, after enjoying two good short rides on Sunday and getting a feel for just how well this bike goes ...

... it stopped going. It ran the battery down and was not charging.

So with an experienced motorcycle electrics friend beside me, we went looked into the problem this evening.

I am not going to share the photo of what we found under the sprocket cover - it would put you off your dinner for days.

Needless to say - since I failed to ensure that the harness from the stator could in no way drop onto the sprocket, that is exactly what happened. It chewed 3/4 of the way through the harness, chomped two yellows, the green and the white to pieces.

Well - after an hour of careful repair work, we had it back together and running well (and charging well) again.

My next challenge is to find a good condition starter clutch. I am on my second clutch now and the starter still chatters and fails to grip when the engine is cold, I am confident it is all installed correctly - just seemed to have ended up with two well worn ones.

Unless someone has a tip on making sure your worn starter clutch works?