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Discussion Starter · #1 ·
Hi guys,

I've been lurking here for 3-4 months and am amazed at what an incredible community this place is.

My story is similar to user 'Chaetophile's (of 'Gods help me, I just bought a bike.' thread). I am very new to all of this, in fact I only just my CBT in January (that's Compulsory Basic Training that you need to do to ride any bike at all on the roads here in the UK) and am about to do my full bike license in a couple of weeks. That of course hasn't stopped me from diving in a buying a bike. The one in question actually belonged to a former member of this forum so you might recognise it.

It has a LOT of miles on the clock (90k), so my plan is to take it very slowly, read carefully through as much of the reference material as I can, and take it one step at a time. Hopefully this thread will serve as reference for all the inevitable mistakes i'll make and as a place for me to post pictures as and when I do things.

As mentioned the bike has seen a lot of road, but actually runs pretty well. That being said I want to take her completely to pieces and rebuild her from the ground up. No point putting lipstick on a broken pig (that's a phrase right?). To that end, I thought I may as well dive in and start with the engine so tomorrow I'm going to drop the engine out, and then see where I get to (again, with the help of some reference threads i've seen on here, a pdf engine manual or two and a very battered old haynes manual).

Build wise I'm unsure what i'm doing yet (something... cafe-ish) but im trying to just stick to planning the aesthetics until I can get the beast reconditioned mechanically.

Pictures of the bike in question below:

Land vehicle Vehicle Motorcycle Motor vehicle Car Vehicle Motor vehicle Auto part Car Motorcycle Land vehicle Vehicle Motorcycle Car Motor vehicle
 

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It may be a better idea to get the bike running properly and ride it for a little while to confirm that and iron out any issues discovered before pulling it to pieces. It's always tempting to start with taking it apart, but by riding it a little while at least you would know for sure that you were starting with a working, running bike with no issues rather than discovering things very far down the track after already having it in a million pieces and finding it hard to troubleshoot.

It would also give you a good idea as to what you may wish to change about the bike; that can really help guide the direction you wish to take it in if you do take the path of modification/cafe'ing/bobbering/etc.

Also, welcome! That has to be one of my favourite colours of CX and mine would still be that colour if the tank hadn't rusted away...
 

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That seems to be a pretty typical UK CX 500 - B, 1981. Motad 2/1 exhaust, aftermarket front fender / mudguard and here and there obvious corrosion. AFAIK is frame rot not at all unknown on older UK motorcycles. Many seem to live outside the whole year and the climate is humid. There has been talk about rusted footpeg "hangers" and rear swings more than once.

90 K mls is much for most bikes but not the end of the world for a CX, provided it has been well taken care of. I have the same or more on both of mine and would easily trust any of them with anything a good motorcycle should be able to do. Maybe not "around Europe tours" but not far from. Check the frame for rot and the motor for the usual things - smooth running, no bad noises, no metal flakes in the oil, Good, stable oil pressure and normal running temp. Then it´s time to decide if the bike is worth putting money on. You shouldn´t need to take the motor apart if it´s healthy.

But - with 90 K - if it hasn´t been done before, it´ll be time for a triple bypass. Also a good idea to replace the oil pump chain with a new one.

For starters..

/Sture

Edit: As usual - typing too slow (or much).
 
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Cheers and welcome Culturalelite!

I've been here for months and have yet to do a lick of real work, other than disassembly and gathering parts. I've learned a ton, though.

I hope you do better than I have!
 

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That's enough miles for just about anything to have worn out, but have to agree with J.C. that it is best to find out what needs fixin' first before taking the whole thing apart now and later discovering that you missed something that could have been discovered while riding it a while, especially since the WIKI is full of info on how to diagnose just about anything you are suspicious about.
 

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Discussion Starter · #6 ·
Thanks guys, great advice all round. I figured It was best to lay out my plan before I began and i'm glad I did.

While I haven't ridden the bike a huge amount, I have ridden it some. It backfires very occasionally (a carb problem?), and has some problems starting up on cold mornings. Overall it doesn't seem to have any big problems as far as I can tell at the moment. As I say it's really just the age I'm worried about. Will follow Sture's advice above and run all the checks before I continue.

I've read quite a bit about the triple bypass, so perhaps that should be my first order of business rather than my overly drastic measures. I think my intention in breaking it down was really just to replace things like gaskets etc, but if it's not recommended then I won't touch that stuff for now.

Frame integrity seems good, i've looked it over pretty thoroughly and all I can see is quite a lot of surface rust.

As mentioned i'm trying to leave aesthetics for now, but am planning on getting hold of Murray's carb kit, modernising the electrics (ignitech), same with fan and then go from there.

thanks so much already, everyone.
 

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The Ignitech doesn't really do a lot if your CDI box and stator work normally, and you lose the ability to dump start the bike with a dead flat battery. If certain parts of your stator are fried, the Ignitech can be purchased as an alternative to dropping the motor and replacing the stator.

Carbs are likely dirty! Do you have access to an ultrasonic cleaner? Or will you just leave them be until you replace them with Murray's carbs? That's certainly a tempting way of doing things as it means you start with fresh carbs that are good to go...


...speaking of the carbs being dirty, how is the fuel tank? Any rust or debris inside? Check the petcock screen and make sure you have an in-line filter, else you'll likely clog up any cleaned carbs quick smart.

With Murray's carbs... are you planning on ditching the H-box? Got a plan for replacing that section of pipe?

Frame integrity being good is a great start.
 

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Discussion Starter · #8 ·
Thanks JC,

I guess I have a lot of testing and diagnosing to do before I start hitting the thing with a wrench. I'll get testing the stator for sure.

Fuel tank seems clean which I was very happy about. Will check the petcock screen tomorrow along with the list of everything else i'll be looking into.

So, with Murray's carbs, yes I was considering getting rid of the hbox and the airbox and using some pod air filters.
 

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Sounds good. Also check out the technique of viewing your cam chain tensioner with a dental mirror or such. That's for the manual tensioner models, anyhow, I've never tried it with an auto tensioner bike.

Oh, and put the bike year and model in your forum signature!

Wait, what year is it? I didn't see it above. If it's a CX with TI ignition you have a different stator/ignition setup so you wouldn't need the Ignitech anyhow :)
 

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Frame integrity seems good, i've looked it over pretty thoroughly and all I can see is quite a lot of surface rust.
Zooming on on your photos, it looks like the left-hand footrest/exhaust bracket has possibly been replaced with a piece of flat steel plate - the shape somehow doesn't look like the original. The original (hollow) bracket here often rusted out (as did the one on the other side), so the frame may well have serious rust inside other hollow lower frame sections, including the swinging arm. As these are fairly out of sight, yet get wet/salty, they are a common failure.
 

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If the compression tests good, leave the heads alone. The timing chain and oil pump chain are a good preventative measure, as well as the clutch springs if they're under spec.

With the 2-into-1 exhaust, there's no h-box to remove. You'll want divorced 2-into-2 with Murray's carbs.

I think I see an upper rear engine hanger in the pics, in which case it won't be TI.


R
 

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My Opinion

Do a full tune and maintenance,starting with adjust and inspect timing chain.

If the timing chain is good continue.

If it done do the chain and water pump.

I wouldn't be surprised if all was good inside.

They don't get that kind of mileage by being abused and neglected.

The thing that would be next would be to find an icepick and a flashlight.

Get the bike up where you can give it a thorough underside inspection.

Familiarize yourself with the frame a are and swing-arm most prone to rust through .

Poke the pick in all those places you may find holes or some green or brown gunk has

been put in the frame,if you do good for you because that stuff is anti-rust treatment.

If there are gaping holes or the pick goes thru in spots you wil need to repair or replace as needed.

Then fo from top to bottom front to rear and check everything. The FSM has maintenance schedule

use it as a checklist.

It is not absolutely necessary to replace the 2 into 1 there is a slight difference in the power band

than true dual exhaust. Consult Murray

I like to get the most bang for the buck,wouldn't it be nice if no major repairs were needed.:cool:

You could just do cosmetics and order that set of carbs. and get right to the fun part.:icon_thumbright:
 

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Discussion Starter · #14 ·
So just a short video of me starting her up.


Checked over the frame as well as I can without stripping her completely down and hoisting her off the ground (which I don't have the kit for ATM). And as near as I can tell she's been really well cared for. As you can hopefully see most of this is just dirt (i've given the frame a good prod all over, especially on the surface rust bits.

Swingarm from the side (a lot of dirt, very little rust)
Auto part Tire Automotive wheel system Automotive tire Wheel

Underneath the swingarm
Architecture Tints and shades

Radiator seems to be the worst rust-wise, but again this seems to be mostly on the surface.
Auto part Engine Vehicle

More of the swingarm and frame
Cartoon Illustration Fictional character Line art Drawing

I took some bits and bobs off, but mainly so I can start doing the checks. Going to start working my way through my checklist later today.
Land vehicle Vehicle Automotive tire Motor vehicle Tire

Soooo.. as suggested I'm going to start by looking at the cam chain, but my inspection port appears to have this connected to it, which is connected to the airbox. According to google its a crankcase breather and common on later model CX's in certain regions.
Auto part Automotive engine part Engine Carburetor Fuel line

Onwards and upwards. Thanks for all the advice so far guys.
 

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Discussion Starter · #15 ·
Hmmm some weird auto-rotate on those images. I am sucking at photos and video today.

Also a quick shot of the inside of the petrol tank. A very small amount of rust. Is that amount anything to worry about? I guess really I need to check whats coming out the otherside to make sure there's nothing sitting in the bottom of the tank.

Auto part
 

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Take it a little easy with that breather bottle - especially when tightening it again! They´re a little brittle. 22 mm (if memory serves) spanner and just a little more than fingertight. You don´t have to ask me how I know! And they´re not always so easy get, again. I believe they´re NLA from Honda.

Looks as if you have some fun waiting (not being sarcastic).

/Sture
 

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"Soooo.. as suggested I'm going to start by looking at the cam chain, but my inspection port appears to have this connected to it, which is connected to the airbox. According to google its a crankcase breather and common on later model CX's in certain regions."
That breather is indeed the inspection port on your (and my) model. I had to think twice about this too as it didn't seem to be mentioned anywhere I looked. Undo the hose clip, pull off the hose and unscrew the metal tube thingy (technical term...) and Bob's your uncle. Sounds like your new baby is pretty sound. Get her out on the road and enjoy!
 

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Check valve lash adjustment.
You will want to check compression and do a leakdown test to convince yourself you don't need to do a valve job and/or pistons.
Right now you have a runner, that's good, but do the above before you pull the engine for the triple bypass.
 

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I like it! It sounds fair, and the frame look fine from the pictures. 90k is a fair amount of mileage, and I always wonder where the bloody hell vehicles like this travel to, on an island where you can get to the other side in a day (if you make good time).

Indeed, as PCD has mentioned, one of the footrest hangers has been replaced. Looks a good job though. It is indeed a poor area for rust in this country. I haven't looked, but I gather there aren't any pin sized drain holes on the underside of the original ones. Mine are looking a bit scabby too. I need to get on them soon. I sometimes think I should just weld over any 'breather' holes in the frame and just fill it with oil or Waxoyl..

Also, look out for rust around the breather holes that are located at the rear, right paralell to the shock on the subframe, I had a big hole develop on mine that needed to be welded up. It tore me as I proded and proded and made the hole bigger. But welding a nice plate onto it resolved that!

A good tip for cleaning your carburettors if you've not got an ultrasonic cleaner...

Go to the supermarket, (any, they all have them) and get a couple of bottles of pure lemon juice. They're like 60 pence a bottle. Then get an old but tall saucepan. Disasemble the carburettors, take out the plastic bits, brass, and rubber, and boil the caburettors in the saucepan with the lemon juice. Works a treat, you should see the result, and also see the gloopy black stuff at the bottom of the saucepan when you're finished. Re-assemble, mount, balance carburettors.

Looking at the pictures again, i've noticed alot of the engine bolts have been replaced with allen key bolts. It also has the larger diametre filter cover bolt i've noticed.

Just a mention of gaskets, you don't really need to replace them unless you disturb them. And even then sometimes you can get away with re-using them if they don't split at the bottom. Horses for courses stuff, but that's my opinion.

Anyway! Nice bike! And as someone who had to go through the absurdity of what is the forced European legislated hoop jumping that is the motorcycle test, I just have to say, good luck, have faith, be positive, don't give up. Don't let the ECC system overcome you! Of course, I don't know how old you are, so depending on which margins you fall between the hoops may be higher or lower.
 

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Discussion Starter · #20 ·
Sture, Chillpill, thanks guys. I took it off very carefully without issue, although there was a small amount of white gunk in it which worries me slightly. I couldn't do the cam chain check after all as my small mechanics mirror doesn't fit inside the port. I've bought another small dental mirror off ebay so I can properly inspect it. If I end up scrapping the airbox, what do I do with the crankcase breather setup?

Thumper, thanks. I'm on it. See below.

Blurredman. Thanks for the tips and advice. I don't have an ultrasonic cleaner, so the lemon juice tip will definitely come in handy but I am planning on picking up one of Murray's carb kits so hopefully I shouldn't need to clean my carbs. I didnt see the drainage holes when I was inspecting today, but will definitely check that out now. You're right a lot of the bolts all over the bike have been replaced with hex bolts which I guess is a good sign it's been well-cared for an potentially overhauled before. Bike license stuff, yeah i've done the CBT and the theory test and booked in for a five-day course now to get my full license (i'm 34, so there's no major barriers).


So, my ever changing plan for this week is (as I gather the tools):

- Engine pressure test.
- (I'd like to do a leakdown test, but I don't have access to the equipment needed currently)
- Cam chain check.
- Valve adjustment (bought a feeler gauge set today)
- drain the oil and check it.
- Drop the engine out.
- Triple bypass.
 
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