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To Fix Or Not To Fix Or How To Fix

I know I've covered this before but the CBF125's oil consumption is now, well, frankly, alarming. I check it roughly every 150 miles and I'm often putting in 200-300ccs of oil. I'd estimate in those 150 miles I've used say 5 litres of fuel which means it's running on roughly 5% oil. That's more than most 2-stroke's 2-3% oil mix.

So what do I do?

I could, maybe should, just leave it alone. The bike runs fine, it starts fine, the fuel economy is fine (save for the oil cost) and as long as I keep on topping it up at present there's no suggestion anything will go wrong. There is no point in fixing things that aren't broken. 

Ren's CBF in 2013 when it was still quite new and clean
Cor! I remember when it was new to me with about 6,000 miles on it.

But. The only real issue is this alarming consumption prevents me from using the 125 for anything other than local runs. It's fine to go to Sharon's, maybe a day out in The Trough of Bowland or even North Wales. Anything more than that will require me to carry a litre of oil with me. If I were to go on a tour I'd have to purchase more oil as I travelled. I'd be worried about drying out the motor if I didn't stop to check it often.

I have the 500 though. There's no real problem using the 125 for the local stuff then using the 500 for the tours. I'd just like the option. I'd just like the chance. 

I could fix it up. For the staggeringly stupendous cost of - ready for this - £39 I can get a NEW piston and a NEW barrel/cylinder and a NEW set of rings and a NEW gudgeon pin and a NEW head and base gasket. That's just bleeding ridiculous, I couldn't buy the metal to make it for that price.

Of course this will not be genuine Honda, this will be a Chinese copy of some description. Whether or not it meets Honda's exacting standards is unknown but at that price it's got to be worth a shot. Sharon's Keeway clearly demonstrates that the Chinese can and do make some good stuff.

A genuine Honda barrel is prohibitively expensive at £370, 9 times more than the complete kit!! I would do better to buy another engine at that price and throw it in, job done. I could then strip the old motor at my leisure, more out of curiosity rather than need. It will be interesting to see what an 87,000 mile 125 engine is like inside.

The piston on Ren's CBF125 but way back when it was still quite new
I wonder what it looks like now inside the engine's top end?

The problem with a new motor is - is it worth it? While the bike is still sound the rust mites are taking their toll and everything else is quite aged. Would it not be wiser to put that £350 - £400 for a used motor towards a much newer CBF125 or CB125F? I could end up with a 1,500,000 mile 125 rather like "Trigger's Broom" (8 frames, 12 engines, 4 tanks, 6 seats...)

Then there are various shades in between all this. Used piston and barrel but genuine Honda? New genuine Honda rings? New pattern rings? A rebore and oversize piston is pointless at these prices. I suppose IF IF IF I decide to fix it the first thing is to strip the motor to see what is worn and what needs replacing.

So the first question is - to strip or not to strip? Keep lobbing oil into it or start the process of fixing it? Remember I am not a retired gentleman of leisure. I can't take an age for this task as I don't fancy commuting on the 500 and leaving it parked outside the office.


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Reader's Comments

Upt'North said :-
I'd leave it alone for now and if and when it goes Caboom! Put the Chinese kit on it.
I'm guessing you're not using expensive oil and there's no need for oil changes either. Although it may still be prudent.
If the Chinese kit is made from cheese and lasts one trip, so be it. Then you can Bury it in the back garden along with all the other bodies.
Upt'North.
27/01/2020 02:10:39 UTC
Ren - The Ed¹ said :-
What makes you think I'm not using expensive oil? No, but cheap oil ain't cheap these days. I'd struggle to find even the most basic of 10w40 for less than £15 for 5 litres. Eeeeeeh I recall 20w50, 5 quid for 5 litres.

Just as a note to anyone reading - don't use 20w50 in the CBF125. The conrod big end bearing has a needle bearing not plain bearing. The suggestion given to me is that the thicker oil can't get out of the way of the needle bearings fast enough causing a pressure wave in front of the needles. This is what eats the crank. I have no science behind this or proof although Honda did set it to 10w40 for a reason.

Bury it in the back garden? Look, right ok, we know Mrs North made you put fence posts into your back garden so she could spend the savings on shoes, but we common folks don't have GARDENS! We have a small back yards covered in concrete flags, beneath that will be sewers, gas pipes, mains wires, water pipes and the mortal remains of my hopes and my dreams. There's no space here for motorcycles or bodies.

Sharon on the other hand - poor poor Sharon does have a garden. If I ever vanish from the blog would someone be kind enough to check Sharon's garden for "fresh" diggings.
27/01/2020 02:28:44 UTC
John Scotcher said :-
Be careful about using Chinese aftermarket pistons. I bought one from Wemoto for my Yamaha Serow, fitted it and the engine seized after about 5 miles. On examination by an engineer, he said the piston was not even barrel shaped as a piston should be. Basically, it was tube shaped which does not allow for different expansion rates on the piston. Needless to say, Wemoto didn't want to know, saying that they had never had any problems with them but they stopped selling them on their website after that!
27/01/2020 02:51:07 UTC
Ren - The Ed¹ said :-
It's a tough call John Scotcher. I am aware there is some really rather nasty poop out there, but then Sharon's Chinese Keeway has 24000 miles on it with no issues and the quality is excellent. I have absolutely no way of working out those which are good and those which are bad.

I could take the philosophy that "it's cheap, worth a shot eh", equally valid is "buy cheap, buy twice" which also translates to "buy cheap fit it remove it buy expensive fit it all again bike off the road for ages...".

Maybe I just keep throwing oil in it eh.
27/01/2020 04:25:04 UTC
Snod said :-
If it were me I'd scour ebay for a cheap, low mileage Honda barrel and piston. If there are none which are cheap enough then set up a saved search and keep checking.

Alternatively if the gearbox is giving any bother then I'd be looking for another motor.. On the cheap of course.

~250ml of oil every 150 miles is so bad that even I, a TRX850 owner, would find it strange! Does it smoke? Does it make Sharon feel sick if she follows you for more than a few miles?
27/01/2020 07:57:17 UTC
ROD said :-
I think I would go the all or nothing approach.
Just keep topping it up with oil until something needs fixing, and hope it is not serious, or take the engine out and do a complete rebuild which will then last many miles.
If you just replace the top end, surely you will be wondering what state the rest of the engine is in after 87,000 miles.
The logical question must be 'Do you want to keep the bike, or do you fancy a change?'. If you want to keep the bike and a rebuild is viable, do a full rebuild.
27/01/2020 09:20:23 UTC
nab301 said :-
Ren, maybe a set of oversize rings in a std bore , maybe the valve guides and or stem seals are worn.... Looking aparts lists it looks like the L/h main bearing isn't replaceable ( crankshaft replacement only )so maybe ride until it stops, maybe a new((to you) bike would be cheaper.....
Nigel

27/01/2020 10:51:34 UTC
Ren - The Ed¹ said :-
Snod - what surprises me is that I'd expect to be followed by a cloud of blue smoke and a collection of environmentalists at this rate of burning oil. And yet no, it runs clean, no smoke on startup, no visible smoke when running. It's as though it has a leak. There is a minor weep at the cylinder head but nothing more. It's as though someone is just taking oil out the motor at night. CONSPIRACY!!

The problem folks with a major or even minor rebuild is time. Top end, bottom end, rings, valves, whichever I do will take time. Presently the bike is in use 5 days a week for commuting. I dare not use the 500 as it's still too new to leave parked outside the office. The 125, being a dog, is unlikely to attract the attention of professional thieves.

It's not like I could use Sharon's 125 while I work on my own as there's not enough space to move if there's 3 bikes in my shed. Anyhow Sharon would kill me if I got her bike nicked. I could use Sharon's bike and leave my 125 at hers where there's space. Bit of a long drag to go and work on it though.

Hmmmmmm. listening to myself I know what's going to happen I suppose. I guess as ROD suggests just keep riding it till something goes pop then cross all these bridges at that time. Will I get a new (to me) bike, a replacement motor, a replacement motor then rebuild the old one, take up cycling, quite work and live in poverty?

Here's an idea just popped into my head. Buy a replacement motor but store it ready to be fitted as and when this current one goes pop. That way swapping the motor won't take the bike off the road for too long, I'll have the old motor to strip down, play with and possibly recondition. If the cycle parts let me down before I get to fit the fresh motor I can always sell the fresh motor again.

Hmmmmmmmm. You know I used to be very indecisive, I'm not so sure these days.
28/01/2020 10:12:28 UTC
Bill said :-
Have you done a compression check dry then oiled to establish it is bore/ring wear before deciding. Valve guides usually shows as smoke on overrun. When the crf was using oil any one riding behind could smell it even when they could not see the smoke.
28/01/2020 06:59:03 UTC
Ren - The Ed¹ said :-
Good call on the oiled/not oiled compression test Bill. Easy to do and may help with grasping what in particular is worn. I've never done valve guides before. From what I can tell it's a job for the engineer's workshop, apparently you can't just tap out the old ones and tap in the new ones?
29/01/2020 09:27:03 UTC
Upt'North said :-
Ed of the yard, the back yard, yes you Ren.
Valve guides, I haven't changed many and none on a bike but I seem to remember on Gardner diesels that's exactly what you did; number 2 hammer and drift of some sort to whack the bejesus out of em.
May not have been best engineering practice though.
Upt'North.
29/01/2020 12:53:37 UTC
Ian Soady said :-
Valve guides on the kind of bikes I ride are easy enough - warm the head up and use a stepped drift to knock out the old ones and knock in the new. However, I suspect that the alloy in your head is not the most robust and it probably doesn't have the meat around the guides to support this method.

Whenever you fit new guides you "should" recut the valve and seat although I'vew got away without.....
29/01/2020 12:55:37 UTC
Bill said :-
The 230 which is a very similar motor has valve guide seals, it can be done without removing the head, piston at tdc compress spring and valve will not drop much. Rubber band on valve to hold it fully up on assembly, easily removed afterwards Cheap trial fix. I found more economic to buy a 2nd hand low mileage (comparitively) head rather than changing guides.The company who rebored the barrel had an accident and broke it and very kindly replaced it with a new genuine Honda with piston so should last many more years.
29/01/2020 04:07:03 UTC
nab301 said :-
Presumably, looking at the cost of an OE replacement exhaust the CBF has a catalytic converter somewhere in the system which would probably explain the lack of smoke although if it's burning as much as you suggest the cat is probably well on the way to being damaged. If it's burning two stroke amounts of oil (even 50:1 like my EM Zed)it (oil) would be dripping out of the exhaust at this stage like any other two stroke I've owned. ... I have tapped valve guides out of alloy car cylinder heads and replaced them by cooling the new guides and heating the cylinder head but as Ian suggests I always required the use of a valve seat cutter afterwards which meant a trip to the engineering shop.
Also , on my recently mentioned race imp I used to routinely do compression tests after each event to preempt any loss of performance , so when I detected loss of compression I carried out the text book wet compression test that Bill suggests and it ( cured ) the loss of compression, but in my case the loss of compression was valves and seats. I guess at slow cranking speeds the oil will seal these too. Hopefully it may just be the Stem seals . Maybe a cheap borescope would allow invstigation without too much stripping?
Nigel
29/01/2020 09:36:40 UTC
Ren - The Ed¹ said :-
Whenever I see, read or hear of someone replacing the valve guides there's thing thing where you are supposed to "ream" them to size. From what I've just researched the utterly correct thing to do is fit the guides which should be oh-so-slightly tight, rig the head up under a drill press at the right angles etc etc and use the reaming tool to ream the guide to the exact tolerance and precise perpendicularity.

But most in the forums say "it'll be reet", "it'll ream itself in", "just stick the reamer in a hand drill for a few seconds" and so on. So er, I'm non the wiser.

I can do the valve stem seals no problem, I have a valve spring compressor.
29/01/2020 09:49:46 UTC
nab301 said :-
All of what you say is true which is why I generally leave it to professionals. As to "reaming itself" , I stripped a head off a car engine which had been running nicely ( to cure an oil leak ) and discovered a previously bent valve ( presumably a cam belt broke ) Everything will bed itself in if you leave it long enough I guess!
The problem I've had locally in recently years is the demise of engineering shops and especially the demise of shops willing / able to tackle bike engines . I left an Enfield Bullet barrel in for rebore and a cylinder head in for new guides and exhaust seat but it took nearly a month for them to complete the job and it felt like they wanted to bill me for the entire months labour too...
Nigel
29/01/2020 10:31:08 UTC
Ren - The Ed¹ said :-
In all my time spannering I was about 20 when I last used an engineer's workshop to skim the head from my mother's Cavalier. As such I can't speak of how many engineering places there are these days. I do know there's a place just around the corner from where I work that does car engine stuff, I've never asked about bike stuff.

I suppose we live in a time where engines are in fact quite reliable and cars are considered more of a consumable than back in the day. Things have changed, when did you last see a TV repair man and washing machine fixers are few and far between. The engineering shops that remain will likely do work for enthusiasts with vintage or racing or performance machinery.
30/01/2020 08:57:38 UTC
Ian Soady said :-
There are still plenty of those engineering places around, at least in the Midlands. In my new leafy abode of Redditch there is an excellent place called Nametab which will tackle any sort of job. They do specialise in 2 strokes but don't hold that against them....
30/01/2020 10:25:45 UTC
Pocketpete said :-
Hmm all that work for a bit of oil loss. I knew you were tight but its only oil ren.
30/01/2020 11:14:10 UTC
Ren - The Ed¹ said :-
Have you moved Ian?
BIT of oil loss Pocketpete? BIT?!?! My concern is drying out the sump.
30/01/2020 11:33:12 UTC
RobEll said :-
Hi Ren, just a thought but when my old off road, long-toothed XL250 farted it's last it was haemorrhaging oil via the final drive output shaft oil seal. Maybe worth a looksee bit likely already on your have-checked list. In other news: My little Keeway RKV 125 is banging away better than ever at 15000 miles in 17 months and only a few minor fixes for rear caliper dragging (clean piston/caliper every quarter and done), and shield (duct tape) some wearing wiring sheathing. Love that little bike, and much of it is way over engineered e.g. massive upside down forks and frame from the previous RKV200, only the thin paintwork or electronics are unknowns so far. Much cheaper to fix than my ageing car which costs at least £300 every visit to the mechanic...with ever more alarming frequency.
05/02/2020 09:30:35 UTC
Ren - The Ed¹ said :-
There's no oil on the floor around the bike and no serious oil leaks. There's a weep from the head gasket but the oil dries out before it even starts to dribble it's that slow.

I'm glad to hear the RKV is doing well! Do you use it in all weathers? At just shy of 1,000 miles a months I'd guess you do. And find me a bike that's used regularly and doesn't require the brakes servicing all the time. I used to own a CLR125 City Fly fitted with an supposedly "cheap" Grimeca brake. It was loose, rattly, the pistons weren't so tight and the paint flaked off. But BECAUSE it was built to low tolerances it never seized up and worked a treat. Here's to slack brakes.
05/02/2020 12:46:54 UTC
RobEll said :-
Ah, I thought you'd have considered it, the oil leak on that old Honda was
much increased with the engine running but had more than one oil leak! And yes in all weathers getting to and from Bristol 3 days a week from South Wales for work, a salty business in Winter. I'm a little lazy with the daily (read weekly), bike rinse and it's faring very well on rust front but it is garaged. I've been swapping some parts across from RKS bits which seem a bit easier to find & cheaper, sprockets and the like - these bikes are just SO cheap to buy and run, and everyone likes a bargain! The cheap transport sector of the bike market has been well and truly revived by the recent influx of Chinese commuters, they could teach the big Jap 4 a thing or two, looking at the new super cub for around £3k...
06/02/2020 06:17:08 UTC
Ren - The Ed¹ said :-
It does strike me as odd that while the Chinese are creating "affordable" motorcycles with ever improving quality Honda decided to market their revamped cub to the modern trendy stylish riders.

I suspect it's like this. Honda UK would rather do business with a small group that will buy the cub as a style statement rather than a throng of spotty oiks who'll thrash the bikes leading to questionable warranty claims and a bad reputation. I'd find it interesting to see the price point and marketing in the growing economies like Thailand or Vietnam where the original cub powered the whole country.
07/02/2020 02:15:46 UTC
RobEll said :-
I know we're likely a dying breed but the sparsity of 'affordable' offerings under £3k by any of the big Japanese/European crowd is deafening. I understand that this depends on one's definition of affordable of course. And they may wonder where their diminished sales base has gone to in recent years...will the last biker pls switch off the lights and lock up? With the burgeoning oil/climate/housing affordability/take your pick of disasters; as you've aptly pointed out, small capacity bikes (should) be the future.

In any event at least some brave, overtly Chinese-built brands are stepping up and filling the spotty oik (potential new biker) gap for the present...and put their money where their mouths are. Perhaps the (ostensibly) Japanese manufacturers' bike offerings have now plateaued and the Chinese really may dominate the future - Who knows? I for one have an eager eye on the Lexmoto >125cc machines like the LXR380 et al, they seems to have the right mix of power and looks for the A2 lot, and the spotty whatnots need stepping stones to reach for if they stick with the bike bug. They are building brand loyalty imho. Apologies for the ramblings!
07/02/2020 08:49:57 UTC
Upt'North said :-
You can't maintain the dealer margins in the One Make luxurious emporiums and sell bikes for peanuts too.
When you walk into a franchise these days it's obvious where the profits go.
When I take my Beemer (car under warranty) in for service there's a Coffee and Danish in my hand before I've got to the service desk. Then when I say I'll wait for it a freshly made sandwich and chocolate éclairs arrive. That'll be another pony on the bill then.
Upt'North.
08/02/2020 10:33:12 UTC
Ren - The Ed¹ said :-
Lexmoto have been around long enough now to establish a dealer and parts network I guess. I am aware when looking for bits for Sharon's Keeway there's Lexmoto stuff everywhere. Be fascinating to watch them move into the midrange models.

And yes, much like the spotty oiks of yesterday the current batch of engine thrashing chain rusting wheelie popping reprobates will eventually lead to becoming fat middle aged bloggers moaning about the youths of today and their poor maintenance skills. When I look back I shiver in abject terror at my young self, best not do that too often. My dad says he still does it at 75 looking back to his 50s and 60s.

You drive a BMW that's under warranty Upt'? If you can afford their service prices you've earned your dinner from them. I take your point, you can't have shiny showrooms with shiny sales folks in shiny uniforms at bargain prices.

Speaking of (not) looking back - I recall when main dealer motorcycle shops were more akin to engineering sheds with a large oily wooden counter and a surly chap smoking a roll up asking "waddya want?".
09/02/2020 06:53:10 UTC
Ian Soady said :-
Yes, it makes me smile when people regret the passing of the old style bike shop. All I can remember is queuing for hours in Vale Onslows on a Saturday morning only to be told by said surly bloke they didn't have the crucial part I wanted as "there's no call for them".

For all their faults the WWW and ebay have made life so much easier.
09/02/2020 09:57:22 UTC
Ren - The Ed¹ said :-
There were pros and cons to the old bike shops. If for example I need a choke cable. Today it will have a specific number for my model of machine and that is the only cable they'd supply. Back 'int day if the surly chap was in a good mood he'd bring out a selection that "might just do the trick". Equally though it was all too easy to be sold a part in a dusty box that's been on the shelf for years and was turning to rust or crumbling.

'Tinterweb does have it's advantages - and disadvantages too. If it exists in the world you're likely to find it online. Then you'll have to run the gauntlet of lost deliveries and parts not as shown or described.
09/02/2020 05:43:54 UTC
nab301 said :-
The internet is handy for research and for items you're not in a hurry for but there was one shop in Dublin ( unfortunately became a victim of the recession in recent years ) it was there since the 50's . I started using them from the mid 70's , bought my first helmet , my first wax cotton jacket! They had everything , even engine components for all makes .One of my first bikes was a Honda S90 ( centre tank) . It needed a camchain and oil pump drive sprocket , I expected to have to go to a main dealer but they has the lot ex stock. Even in the early noughties i was looking for (mikuni) jets to suit an Enfield 350 I had at the time , the storeman shuffled off and came back with an assorted box of jets! They also had an engineering shop for rebores and the like .
Nigel
09/02/2020 08:43:29 UTC
Ian Soady said :-
Way back in the 1970s there was a spares shop in Smethwick (if I remember correctly) called Globe Cycle Spares. Run by an old (then) bloke who rode a sit-up-and-beg ladies' pushbike to work. It was a real treasure trove of what would now be called "classic" bits as well as a load of modern junk. The best bit was all the prices were in £sd on card labels attached by bits of string - and they hadn't been updated since they were put on the parts which may have been decades earlier. Inflation? What's that?

Not only that but the proprietor would add all the pre-decimal prices by hand (pencil on the corner of a cardboard box or whatever) then convert to decimal. It was worth going there just for the experience.

Sadly he died - probably in the mid 70s - and his stock was taken over my a classic dealer and of course repriced.
10/02/2020 10:13:49 UTC
Ian Soady said :-
Oh, and re the internet and speed - I often get items from ebay etc the day after ordering them. Beats riding / driving for an hour then standing about only to be told the bit has to be ordered.
10/02/2020 10:15:19 UTC
Upt'North said :-
Ian, on the subject of real money, do you know crisps are 15 shillings a packet in public houses. 15 shillings! Don't tell our Ed.
Upt'North.
10/02/2020 11:01:35 UTC
Ren - The Ed¹ said :-
According to Google a shilling is/was worth the equivalent of 12 modern pence. So 15 shillings would be £1.80. I was thinking of travelling up to Wooler sometime in Spring and taking in the wonders of Northumbria and maybe even tapping up Upt' for a brewski. Having now discovered that crisps are £1.80 in the pubs I shall be looking to find a cheaper destination.
12/02/2020 09:25:38 UTC
Ian Soady said :-
Google is wrong again then. A shilling (12 old not new pence) was one twentieth of a pound ie 5 new pence. So 15/- is £0.75.

I eschew Google for many reasons and now use duckduckgo - a far superior product and one that doesn't deliver "tailored" ads to me.
12/02/2020 10:22:13 UTC
Upt'North said :-
Thank you Ian. I think he's got ice in his ears.
Poor Ed.
Upt'North.
12/02/2020 11:21:53 UTC
Upt'North said :-
Ed, the kettle will be on. I'll charge you in NEW money to keep it simple for you.
Poor Ed.
Upt'North.
12/02/2020 11:25:10 UTC
Ren - The Ed¹ said :-
Eh what? Can't hear ya'll cos me ears is full of hailstones.

So that's 12 old pence. Right. I wasn't even born when decimalisation happened so while I'm aware of such a thing I have precisely no real world experience of it. 75p for a bag of crisps? Looks like Upt' could get a visit after all. Sorry Upt', tell me where's the best place to park where you won't gripe about the bike dropping chain lube oil?
12/02/2020 11:53:49 UTC
Bill said :-
Ren you are post decimalisation 1971, you have had a hard life. That's makes you just grumpy rather than grumpy old man :-).
Thought this may help with the calculations crisps were 4d (old pennies) there were 240d in a pound and the salt was in a little blue bag inside.

Posted Image
12/02/2020 09:40:19 UTC
Ren - The Ed¹ said :-
We did have the little blue bag of salt crisps, but they were a novelty rather than the norm. I was born in '71 and I'm 48 years old. I consider myself eligible to be classed as at least a grumpy middle-aged man? You know... I was 33 when I started this blog.
13/02/2020 09:18:50 UTC
Borsuk said :-
Those were the Smiths Retro real crisps. In the 60's it wasn't a blue bag of salt but a twist of blue paper. Real crisps they was.
13/02/2020 12:48:42 UTC
Bill said :-
Come on Borsuk, if you twist paper until it holds its contents it's a bag ;-)
Do you remember ever accidently eating the blue paper yuk I blame that for why I hate the taste of salt and don't use it.
15/02/2020 08:11:54 UTC
Borsuk said :-
In the 60’s they came with a twist of paper, in the 70’s they added the salt when making them. Smiths tried making a retro version with a little blue square packet of salt in them, wasn't the same. Not as much salt for a start and they were dearer as well.
Don’t remember ever eating the paper,
15/02/2020 08:24:57 UTC
Bill said :-
Didn't know about the 70s remake I only remember the original 60s version.
You would of remembered if you had bit into the blue paper full of salt, usually in the dark whilst watching the Saturday matinee in the local flea pit as the cinema was affectionately known as and it only had one screen :-). Black Jacks were 4 for a penny and chips were only 4d. Wow it makes me feel old.
Is my cocoa ready matron.
15/02/2020 11:56:09 UTC
Ren - The Ed¹ said :-
Sheeez! Welcome to the Zimmer frame memories blog. Tell me, was everything black and white back then?
17/02/2020 09:00:12 UTC
Bob said :-
If you put a new top end on it you'll knock the crank out in very few miles - been there and done that - a tired old crank under a new piston with all that lovely compression.
I wouldn't put a chinese aftermarket piston in it anyway, it's all in the metallurgy (which I don't think they get to a large extent).
A good low miles engine is what you want. It'll only take a morning to fit and your set.
19/02/2020 03:15:32 UTC
Ren - The Ed¹ said :-
I remember you telling us the tale of some bike you re-ringed and it killed the crank Bob.

Thing is - was it the additional compression or was the crank already struggling? These are the things we'll never know without CSI levels of scientific investigation. As for Chinese metallurgy they seem to have gotten it right on Sharon's Keeway. Admittedly though this may not apply to a (very) cheap piston and rings of unknown origin.

I do agree with the good low mileage engine. Buuuuuuut looking at the rest of the bike...
20/02/2020 10:29:43 UTC
Upt'North said :-
Ed, this is just between us, don't tell anybody else.
But I will take 10% for my trouble. This is my cunning plan, take your slightly used 125 and make it worse, remove all unnecessary nonsense, put a characterful dink here and there, remove any comfort items, paint it with a yard brush and voilà, £2500.00.
No I'm serious, look at this beauty being sold at a town near you and advertised as an historic 124cc Honda and only £2500.00.
Is it me?
Upt'North.
Posted Image
23/02/2020 11:05:12 UTC
Ren - The Ed¹ said :-
I see just a tiny flaw in your otherwise excellent idea. Mine is not a "historic" Honda 124 - yet. As the CBF125 is now out of production (replaced by the CB125F - come on Honda), it will soon become a classic. However we are not there presently. If I can keep the old dawg running for another 11,000 miles it will also become a "Very Low Mileage" classic Honda 124.

I already have a certain "patina" all across the bike so any paintwork would ruin this. The real decision will be style. As you can see from your image "cafe racer/scrambler" are in vogue at present but no doubt that will change soon. Maybe we should lead the pack and generate the "worn out/battered" look? I'm good at that, I know I am.

10% you say? Pffffffft, norra chance.
24/02/2020 09:16:18 UTC
Ian Soady said :-
They used to be known as rat bikes......
https://external-content.duckduckgo.com/iu/?u=https%3A%2F%2Fupload.wikimedia.org...
24/02/2020 10:45:17 UTC
Ren - The Ed¹ said :-
I have a "Rat Bike" trophy somewhere. I was dispatching on my Honda CD200 Benly (goes all misty-eyed) and at that point it probably had about 50,000 miles on it. It had been "altered" in my usual haphazard way but I didn't consider it a rat. The club who organised the rally we were at thought differently.

So Upt', we're going for the new Rat Bike styleeee.
24/02/2020 11:11:05 UTC

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