Author Topic: 1978 Honda CB550 Supersport - My first retro bike rolling restoration!  (Read 13772 times)

Offline woody928

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Ahh my mistake and ignorance showing through, I was referring to the air vent pipes that connect in-between the carbs. I'm assuming that should be 3.5mm pipe then? Typically I have 3.2mm pipe already and will soon have 4mm pipe as well. 

As long as it's not going to have any operational impact then that will have to do for now. I would imagine that ordering a replacement set from the US at a later date to replace all of them so that they are matching would be the solution. It could be that I rejet later with an exhaust change anyway.

Offline s7paul

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I've just bought some hose to replace my old split and age-hardened original engine breather.  Finding that the OEM item is discontinued, I got some of this:

https://www.carbuilder.com/uk/low-pressure-fuel-vent-drain-hose-10mm-id

Fits perfectly, and is a bit more flexible than the original.


Offline motty

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By all means use that jet "for now" but I would be purchasing one to have in the spares box ready for the next time the carbs come apart

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Offline K2-K6

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By all means use that jet "for now" but I would be purchasing one to have in the spares box ready for the next time the carbs come apart

Sent from my Moto E (4) Plus using Tapatalk

I'd like to support the contra view,  in that the jet is really just cosmetically damaged and dressed off with a file will perform as original. The seal and bore being the critical performance elements.

As it's part of the original set ( more of us are holding the view that original brass in good condition is hard to match with replacements) and these running best with accurate fuel metering,  I feel it's advantageous to keep an original.

Offline motty

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I'd like to support the contra view, 
Yes, I seem to be a voice in the wilderness on this particular option. However it doesn't hurt to hear a different viewpoint

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Offline woody928

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Use 3.2mm line for the small inter connecting pipes Woody, little smear of silicon grease/oil on the brass ferrule and they'll slide on easy. They never need to be removed except when the carbs are dismantled and TBH a tight fit is far better than a loose one in this location. I'd advise the same on the new O-rings, I used to fit 1 & 2 and 3 & 4 carb bodies together with the T pieces and the inter connecting tube and fit one pair to the bracket very loosely, insert the spring retention pin between 2 & 3 and then insert the other pair, again very loosely. You could then connect the lifter arms to each carb before tightening the screws up a little. Might be me but I'd fit all the jets etc after getting to this part, the carbs will stand on the tops of the carbs quite well making it easier to work on. I'd put the top covers on last of all.

Check that the 2 screws fitted to the butterfly system are doing their jobs along with the eccentric cam bolt. Instructions in the manual.

Noted with thanks, makes a lot of sense now knowing the function. Certainly lubing the fresh rubber on is no bad thing. Parts supply is certainly slowing me now for sure.

Is it worth getting a tool for measuring the float height? or is is easy enough with a measure?

How are the felt rings fitted to the lifter arms Woody?

They're all good with the exception of this one:

IMG_8176 by Mark Woodrow, on Flickr

Input gratefully welcomed, I feel there's very little that I can do. Again, no idea of its exact purpose.

These bits of rubber are also looking very tired however I've not been able to track down replacements anywhere...

IMG_8070 2 by Mark Woodrow, on Flickr

Haha you've got to love an opinion, I feel as though there's merit to both arguments. I'm going to reassemble as is and see how I can get it running however realistically I'd love to replace it. If nothing else its unsightly even if unseen. At the end of the day I only really care about it functioning correctly....

Offline woody928

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I've just starting making some of the felt washers for the carbs Woody, I'll send you 4 to test if your interested, FOC.

I soak mine in silicon oil as it lubricates the lifter arm thus ensuring a smoother throttle action.

Proper float gauge is always a worthwhile investment, they ain't dear.

Have you by any chance got a brake bleeder, one of those that sucks out the fluid from the bleed nipple? Saw a decent video today of one of those being used to test the float valve seat, connect it to the fuel intake and pump the bleeder, gauge goes up indicating vacuum created, this whilst the carb is upside down and bowl off, if the vacuum starts to drop there is a leak, maybe on the seat to valve area or possibly the O-Ring on the valve seat not sealing. If you spray it with WD40 for instance you can actually see the air being sucked down past the O-ring. We all assume that leaks are caused by bad seating or wrong float height but we all seem to ignore the O-ring as a potential cause.

I couldn't possibly say no to that!  8)

I suppose that's the best bet to try and keep it running smoothly!

True, it's amazing how fast all of these '£20' here and there add up though!  :o I believe I'm correct in saying that the correct height is 22mm?

Very interesting, I have got one however I've never been impressed by it. I've never really found a good brake bleeder that I'm really convinced by, I suppose the issue in itself is making a really tight seal for it to test accurately.

It looks like I won't be making the desired progress this weekend while I wait for the rest of the parts to turn up, patience is a virtue I'm told!

Offline woody928

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Well now you have a use for that bleeder  :D :D You could try sealing off one end of the T piece, connect the brake bleeder to it via a suitable pipe, fit the float valve seat (don't forget O-Ring) and the float valve plus float and pin and then stand on it's head so the float is depressing the pin, then see if you can maintain a vacuum, I suppose like mine it has a gauge on it which increases the more you pump.

If it works maybe you could take a video and show the results so others could copy.

I'll get you 4 new felt rings in the post Woody, let me know how they perform, the problem with them is that they are so fragile, any sideways stress gets them tearing. I'll pre-soak them in Silicon oil as well.

Yep 22mm is right

hahaha I'll see if I can find it, I always hoped it would be a much more useful tool than I ever found it to be. I think finding something suitable to block off the T joint could be entertaining bearing in mind the vacuum that will be created and associated pressure.

You're a legend Ken, I think I'll be deferring the rebuild until next weekend now. I should have your felt rings then and I've just found a rebuild kit with the correct 98 main jet so intend to replace it for peace of mind. I'm going to check the pipe fitment that I have too and see whether I need to order any 3.5mm.

Thanks for confirming the 22mm, I've got a small steel rule so I'm hoping that'll perform the job just fine.

I also had this kit turn up this morning so fingers crossed there will be no more waiting around for any screws!

IMG_8187 by Mark Woodrow, on Flickr

Offline woody928

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Well I feel that I should post something up here, there has been lots of progress made albeit the carbs are still sat on my workbench waiting for the last part to come in before reassembly.

IMG_8270 by Mark Woodrow, on Flickr

The front end of the bike has been stripped, I've already refurbished the front brake caliper. There was a some gunk in there and some corrosion so its been through the ultrasonic and given that there was some pitting to the piston that's being replaced. I just need to drop the new piston and seal in now that its been repainted. The brake MC rebuild kit should be in tomorrow to let me crack on with that too. There was a hideous amount of dirt and grime all around the mechanism so its all been cleaned up now. Guess which ones fuel and which one's brake fluid...  ::)

IMG_8260 by Mark Woodrow, on Flickr

IMG_8248 by Mark Woodrow, on Flickr

IMG_8244 by Mark Woodrow, on Flickr

As if I needed any more encouragement for my new braided brake lines, these had erm seen better days  :-\

IMG_8230 by Mark Woodrow, on Flickr

I also realised that this was never going to be  going in back straight ever again so I'm, waiting on replacements from David Silvers

IMG_8211 by Mark Woodrow, on Flickr

The front forks have been fully stripped and after a battle with the oil seals, they're now free! Much hammering with a pry bar later, after them being extremely stubborn... As you can see the lower threads were looking very sad so I've restored them back to glory and have new stainless hardware to be hidden under copper slip. I'm planning to paint up the lower forks and new seals should be in tomorrow to allow me to rebuild those with fresh oil. The oil looked hideous, it was totally black with deposits in the bottom and smelt horrendous for whatever reason. The forks certainly needed some TLC.

IMG_8280 by Mark Woodrow, on Flickr

IMG_8281 by Mark Woodrow, on Flickr

IMG_8336 by Mark Woodrow, on Flickr

IMG_8339 by Mark Woodrow, on Flickr

I also have a new aftermarket 7 inch headlight and headlight bracket to go on, and am working out my options to install LED indicators to clean up the front end. I know the purists won't like me but I'm looking to modernise the bike in several areas. I will have some work to do on the wiring first though as some of the PO's have made a mess and their standard's are concerning to say the least!

I'm going to have to spend some time with the wire wheels on the front fender to see what comes up however its really seen better days. It's making me feel better about my intentions to potentially take a grinder to it to chop it down and simplify the front end.

IMG_8272 by Mark Woodrow, on Flickr

My new Avon Road Rider Mk2 tyres have also turned up, there was no way the 18 year old tyres were being left so new inner tubes and rim tape are sitting at the ready. I just need to work out whether these are something I can install myself with some tyre irons? I've gone for a 3.25 - 19 for the front and 4 - 18 for the rear which seemed fairly close to stock given the available compound choices.

IMG_8301 by Mark Woodrow, on Flickr

Equally is there any advice around wheel bearings on these bikes? should I be able to recycle whats there or is it best to just replace?

A guy from the farm I'm working on also kindly lent me a compression tester so I've now done that this weekend with the following results (cold test as the carbs are removed)

Cylinder 1 - 120psi
Cylinder 2 - 115psi
Cylinder 3 - 127psi
Cylinder 4 - 125psi

Noting the low figure on Cylinder two this evening I did a further wet test having dropped in a few drops of oil to see what happened and it jumped up to about 128psi so it looks like I have some wear to the rings on Cylinder two if I'm correct? Anything to be worried about at this stage?

I fully intend to conduct an Italian tune up once I've got the bike back on the road just to try and clear everything up and see how its really running but sadly that's still quite a way off yet...

More to follow soon I hope!   
« Last Edit: June 28, 2020, 11:43:17 PM by woody928 »

Offline woody928

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No worries Ken, they've now been received with thanks! I'll be cracking on with those this weekend now I hope. I'll have to wait and see what fun and games now await me.

Thanks for the heads up, I've been remarkably surprised how well the original ones have come up in all honestly, given they're not broken or beyond repairing, I'm happy to just leave them restored and covered in copper grease. In terms of the exhaust, I think I'll let sleeping enemies lie for now. I've got enough to deal with without creating more issues. No doubt I'll tackle them eventually though!

Any input on any of the above points from your experience? 

The good news is that the front forks went back on tonight and I've sorted the mess that was the headlight wiring. Looks of horrible destroyed connectors have been cut out and replaced and I now have a fully functioning 7inch headlight and pilot light so I should be good come the darkness now!   

Offline Rob62

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Wow missed this thread but the bike in the first photo’s looks fantastic... i always liked the look of the F models even though I actually owned a K3 back in the day... that marshall pipe is in deed a period item and looks to be in amazing condition i hope you decide to keep it but it must be worth a few bob if you dont..?. I had the exact pipe on mine and it did sound nice, not too loud. 8)

Offline woody928

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Well I'm long overdue an update here  :-[

My experience tells me that replacing even for new Oe ones is best done before they get too bad, they tend to snap off flush with the head as that’s where the majority of the rust is and being so close to the head you normally don’t see it until it’s too late.

As you can imagine getting one out when it’s snapped off flush is not easy

Advice has been heeded, I've not got all of the original exhaust studs out and have already received replacement stainless ones from the suggested link. I just  want to run a tap through the threads to clean them up before putting the new stainless ones in. 

Wow missed this thread but the bike in the first photo’s looks fantastic... i always liked the look of the F models even though I actually owned a K3 back in the day... that marshall pipe is in deed a period item and looks to be in amazing condition i hope you decide to keep it but it must be worth a few bob if you dont..?. I had the exact pipe on mine and it did sound nice, not too loud. 8)

Thank you very much, I fear you may be about to be disappointed on a couple of fronts, particularly if you're more of a purist though :-X

The exhaust has actually just been removed, the style/fitment didn't fit in too well with the style of build I was going for. As shame as it did actually sound really good. It's in fantastic condition for its age with the exception of a dent to the underside on the pipe on cylinder two which clearly had an  argument with a kerb at some point during its life... Any ideas on what it may be worth? I'm certainly open to selling it now that I've received a sleeker Delkevic system to replace it.

IMG_9027 by Mark Woodrow, on Flickr

IMG_9013 by Mark Woodrow, on Flickr

IMG_9017 by Mark Woodrow, on Flickr

Over the past few weeks I've now managed to fully rebuild and reinstalled the front forks, at the same time the new aftermarket 7inch headlight has gone on with a CNC'd sleeker mount to remove the big factory sleeves. The electrical system has needed a fair bit of TLC in places with some horrendous work completed by the PO. Knackered connections or wires  twisted together with a bit of electrical tape seem to be a staple, however all being well I've corrected everything with crimped brass bullet connectors.

IMG_8435 by Mark Woodrow, on Flickr

IMG_8954 by Mark Woodrow, on Flickr

IMG_8459 by Mark Woodrow, on Flickr

IMG_8460 by Mark Woodrow, on Flickr

The front disk brake caliper has been stripped and rebuilt with new seals and repainted. There's new HEL braided lines and EBC pads to hopefully  improve the feel of things too. While there I've also stripped and rebuilt the MC so short of bleeding the system they're new, I'm hoping my brakes will be working slightly above their optimum!

IMG_8422 by Mark Woodrow, on Flickr

Continuing along the electrical theme I've installed the NOS switch from Ken which looks so much better then the aged US market switch that had been fitted. The problem is that its now made my other switch show its age!

IMG_8660 by Mark Woodrow, on Flickr

IMG_8675 by Mark Woodrow, on Flickr

With the front rim off, I got it stripped down to assess where I was looking at my options for a basic refresh before getting the new tyres fitted. Safe to say I was a little horrified to discover this when I finally got the old  tyre off!   

IMG_8657 by Mark Woodrow, on Flickr

IMG_8770 by Mark Woodrow, on Flickr

IMG_8602 by Mark Woodrow, on Flickr

IMG_8765 by Mark Woodrow, on Flickr

IMG_8768 by Mark Woodrow, on Flickr

I wire wheeled the rim however having looked at all of the rust, looking at a few bent spokes, surface rust on others and shot bearings and retainers, I've decided that none of it was worth risking my life on. I've now sent both rims off for full rebuild. The hubs will soon be clad in new rims with stainless spokes and have all new bearings and tyres to boot. I've keep the stock rim size on the front however decided to bump up the rear to accomodate my 4.0 tyre more comfortably. I wanted to look at bigger rims for more available tyre sizes but really didn't wish to run into fitment  issues down the line so left it  as 1.85 front and 2.15 rear. Fingers crossed that they'll be back in a couple of weeks to refit!
« Last Edit: July 25, 2020, 02:15:25 PM by woody928 »

Offline woody928

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This moves me onto my fenders, I'm sure this will meet with distain from certain people. Both had seen much better days with the underside of both appearing to have been totally battered by rust. An aggressive assault with wire wheels was therefore necessary to beat such an enemy back  before converting what metal was left with Dinatrol rust convertor. This proved too much on one section on the rear bumper which actually went all of the way through ::)

The chrome on top of both was on closer inspection pretty pitted and worn out so I didn't feel bad about my decision to paint them. In all honesty I would have been starting again with new if they were staying. The front fender was been slightly chopped and ground down on the front and rear to shorten it and remove the extra supports. I'm hoping this gives me a more modern aesthetic while retaining functionality and stays as the front fork brace. In the end I as pretty happy with the results.

The rear got a very similar treatment however its remained its full size to hopefully keep me drier in the event of foul weather, particularly considering that I plan to tour Europe on it. All of the huge OEM lighting has been removed to make the way for much smaller modern and brighter LED lighting which I prefer for a number of reasons. Efforts have been made to reuse all of the holes where possible and wiring points so my new tailight is nestled perfectly over the rubber wiring grommet.

Some new LED indicators have however been cut neatly into the side of the fender and are almost unnoticeable until turned on. They're incredibly bright and look great I think.

One of my biggest cosmetic victories has been the removal of the hideous old number plate and replacement with a smaller (legal) historic plate. The rear of the bike is now far more to my taste and dare I say it, modernised it hugely. 

IMG_8548 by Mark Woodrow, on Flickr

IMG_8690 by Mark Woodrow, on Flickr

IMG_8696 by Mark Woodrow, on Flickr

IMG_8697 by Mark Woodrow, on Flickr

IMG_8689 by Mark Woodrow, on Flickr

IMG_8679 by Mark Woodrow, on Flickr

IMG_8730 by Mark Woodrow, on Flickr

IMG_8588 by Mark Woodrow, on Flickr

IMG_8720 by Mark Woodrow, on Flickr

IMG_8875 by Mark Woodrow, on Flickr

IMG_8801 by Mark Woodrow, on Flickr

IMG_8867 by Mark Woodrow, on Flickr

« Last Edit: July 25, 2020, 02:13:20 PM by woody928 »

Offline woody928

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With the old exhaust fully stripped off the cleanup has begun, everything looks very sooted up and I'm not sure whether there is a slight oil leak showing from the cylinder head potentially looking at the below photo?

IMG_9020 by Mark Woodrow, on Flickr

IMG_9025 by Mark Woodrow, on Flickr

The studs could have been far worse however they still gave same fight having been painted in place for some extra resistance. I'm grateful that they all came out in one piece before it was too late. I'm keeping fingers crossed that the new stainless ones with some copper slip will avoid any headaches down the line.

IMG_9023 by Mark Woodrow, on Flickr

I'll certainly be doing a little clean up before the new copper crush gaskets ands exhaust gets bolted up.

In other news, I was very aware how basic the rear suspension felt on my original ride home several months ago now. Clearly something was needing to be done. Being a bit of a tart I wanted something more adjustable given that I have various different uses planed and have therefore picked up a set of TEC's fully adjustable rear shocks. Time will tell whether they are any good or not but they certainly look the part.

IMG_8928 by Mark Woodrow, on Flickr

Having now cleaned up the back end of the bike in most other respects and being conscious of how uncomfortable old bike seats can be I've decided to send off my seat for some TLC. I wanted to retain the originality of the mechanism and didn't wish to cut or weld the frame in the  event that someone wishes to revert the bike back to standard one day. That said the seat will be being spruced up to give it some more character, lower the profile and improve upon the comfort significantly. I'm very excited to see howe this turns out, but have total faith in the company that its been  sent  to having seen their other work.

The carbs were  fully reassembled a couple of weeks ago. Id be lying if I said that a lot of patience was not involved. It was rather painstaking getting it all just so, bench syncing the carbs and also resetting the float heights to get it all just so. Despite this I still managed to pinch the O ring seals on the fuel pipe for carbs 3 and 4 causing a fuel leak having fully rebuilt the carbs and got them on the bike. Thankfully those have now been replaced with a huge shoutout to Julie of here!

I also decided to replace the damaged main jet on carb one for  peace of mind so there should be no dramas there. It was incredible what a difference it made to the bike on first  startup even with no proper vacum sync or balance. I'm pleased to report that it is sounding so much healthier so I'm feeling a lot better. Exhaust to go on next to finish that area up.

This is where the bike currently stands, its felt like one step forward, two backwards throughout and I've gone so over budget and more carried away then anticipated however I'm hoping it'll be something that I'm very proud of and really enjoy around Europe come September.

I've probably missed a lot however that gives you the headline pieces I'm sure and I've already written too much  :-X

IMG_8940 by Mark Woodrow, on Flickr

Offline Rob62

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Don't worry I’m nor a purist, each to his own is more my view.... Looks like you have plenty to keep you busy there... shame about the Marshall pipe, I’ve no idea of its value but it must be very rare to find one in that condition, it would suit anybody who is trying to build a special but in the 80’s style.... I haven’t seen one fitted to a classic honda for decades and I’ve certainly looked at plenty in the last few years...

 

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