Similar problem with my BSA Royal Star 500. Top end rebuild & smoked more than I do when I got it running. Did 250 miles to bed it in. Still smoked & used loads of oil. Turned out to be defective piston rings. When I put the rings in the bores & held them up to the light, I could see light between the bore& the outside of the rings. Another set of "genuine rings sorted my problem" best of luck. Nice hond a by the way.
I reckon a mellow burn up is required up bantam hill & around the lanes ,coming out at the trianglier shaped grassy knoll ,on bend that leads to top village . Then around past pub & village church yard & memorial ,turn left at side of house down lane to A 40. After that right down & around the roundabout & back up the A 40 to home base . If she is still smoking due to oily zorst pipe ,remove it & fill it with a caustic soda mix & hang it up to soak . If engine still belching out oil after all that , start scratching head .👍
I know mate. Grew up on bikes like these. Well, Honda SL100s, then SL125s, then we all went mad and got Suzuki TS125s and TS250s...all for road riding for school, and then any pieces of dirt or grass or sand we could find. Ride safe Chris. Hi from NZ
I put a JP piston and rings in a B44 that smoked like that. The rings would just not bed in. I replaced them with GPMs, honed the bore and assembled dry. Worked a treat.
Excellent 👍 thank you for sharing the video and glad to hear it’s progressing, there is a new video I’ve just noticed and will look forward to seeing it later today 👍
I wouldn't do any careful miles on this bike, but take it to the Black Mountain and give it some stick on lower gears and higher revs going uphill. That are not new piston rings if I remember correctly, they were working with different cylinder bore, so they need some time to get used to different cylinder. Good luck with it, you 'll be OK.
Always had a real soft spot for the XL 250 and 350 The 500 plus bikes were a bit on the beastly side handling wise. Got an old FT 500 sat in the shed in need of much TLC.; Lovely grunty lump always wanted to build a sixties style cafe racer but could never find quite the right frame for it.
Give it a good run to get everything up to running temperature, and the oil left in the exhaust system will burn off. Don't tickle it, work the engine to bed the rings in, and I don't mean rev the nuts off it, work it up hill.
Couple of years ago I had a 79 CB100n (similar engine) with exactly the same issue , pitted bore just before BDC, I just thought long term storage and condensation had caused rusting, didn't affect performance just burning oil like crazy , got a 1 over size piston and honed the bore to suit, worked ok. Now have an 80's CZ 125, let's start it up, see it smokes,,,,,,,
'ave you considered that the transmission oil may be leaching lnto the crankcase ?...which was my problemme with my older Suzuki T20 250cc. SO, after draining/flushing it out, I filling it with Castrol R...and Bob's yer uncle ! Had to reseal the lower-end. Perhaps, you will need to do likewise ?
Hi Amelie, being a Honda, the engine shares it's oil with the gearbox in any case, as most - but not quite all do. Your Suzuki T20, like my Hustler, was a 2 stroke and probably sucking transmission oil in past tired crank seals.
Since it had been apart before he got it, I'm now wondering something similar like a missing dowel on a head stud, some kind of top-end oil feed that's escaping into the cylinder from a stud hole.
Someone else had the oil level too high - I lowered it, but it made no difference. It has been refilled with the correct amount of fresh oil with the top end rebuild, but still smoking.
Similar problem with my BSA Royal Star 500. Top end rebuild & smoked more than I do when I got it running. Did 250 miles to bed it in. Still smoked & used loads of oil. Turned out to be defective piston rings.
When I put the rings in the bores & held them up to the light, I could see light between the bore& the outside of the rings.
Another set of "genuine rings sorted my problem"
best of luck. Nice hond a by the way.
I reckon a mellow burn up is required up bantam hill & around the lanes ,coming out at the trianglier shaped grassy knoll ,on bend that leads to top village . Then around past pub & village church yard & memorial ,turn left at side of house down lane to A 40. After that right down & around the roundabout & back up the A 40 to home base . If she is still smoking due to oily zorst pipe ,remove it & fill it with a caustic soda mix & hang it up to soak . If engine still belching out oil after all that , start scratching head .👍
Damn it, why can't we have bikes like this any more?
I know mate. Grew up on bikes like these. Well, Honda SL100s, then SL125s, then we all went mad and got Suzuki TS125s and TS250s...all for road riding for school, and then any pieces of dirt or grass or sand we could find. Ride safe Chris. Hi from NZ
I put a JP piston and rings in a B44 that smoked like that. The rings would just not bed in. I replaced them with GPMs, honed the bore and assembled dry. Worked a treat.
It will take a while to get rid of all the oil from the exhaust, because it's not being burnt, just heated up and boiled away.
Excellent 👍 thank you for sharing the video and glad to hear it’s progressing, there is a new video I’ve just noticed and will look forward to seeing it later today 👍
I wouldn't do any careful miles on this bike, but take it to the Black Mountain and give it some stick on lower gears and higher revs going uphill. That are not new piston rings if I remember correctly, they were working with different cylinder bore, so they need some time to get used to different cylinder. Good luck with it, you 'll be OK.
Take that for one of your famous bimbles and get that pipe nicely warmed through.
Check valve seals , check piston and rings, it can also be carburetor overflow because valve to floater house is leaking it is a small rubber ring. 🤗
If some dirt come down with the gasoline the bowl valve can not close and create overflow.
All sorted in the end - here is the whole story ...
ua-cam.com/play/PLNiCL5QKptFVkOyxU-ib0B5kIb_KL-D0G.html&si=UIJRUFJMQsaZgZoa
Always had a real soft spot for the XL 250 and 350 The 500 plus bikes were a bit on the beastly side handling wise. Got an old FT 500 sat in the shed in need of much TLC.; Lovely grunty lump always wanted to build a sixties style cafe racer but could never find quite the right frame for it.
New rings as well
Give it a good run to get everything up to running temperature, and the oil left in the exhaust system will burn off. Don't tickle it, work the engine to bed the rings in, and I don't mean rev the nuts off it, work it up hill.
I wouldn't lay a spanner on hat engine until it's had a good long hard run - not thrash ed or lugged , just made to work.
Thanks Paul.
I Had an XL 250. the hard chroming went on the cam but otherwise it was a great bike, I hope this came right for you.
Couple of years ago I had a 79 CB100n (similar engine) with exactly the same issue , pitted bore just before BDC, I just thought long term storage and condensation had caused rusting, didn't affect performance just burning oil like crazy , got a 1 over size piston and honed the bore to suit, worked ok. Now have an 80's CZ 125, let's start it up, see it smokes,,,,,,,
Second ring in a honda must ne instslled with markings up if n0t it will smoke a ton. Second ring is tapered taper must be down
'ave you considered that the transmission oil may be leaching lnto the crankcase ?...which was my problemme with my older Suzuki T20 250cc. SO, after draining/flushing it out, I filling it with Castrol R...and Bob's yer uncle ! Had to reseal the lower-end.
Perhaps, you will need to do likewise ?
Hi Amelie, being a Honda, the engine shares it's oil with the gearbox in any case, as most - but not quite all do. Your Suzuki T20, like my Hustler, was a 2 stroke and probably sucking transmission oil in past tired crank seals.
@@paulhenshaw4514 Exactly...THAT was the issue which I just failed in explaining in an understandable fashion.
hi Paul i have always read about BON-AMI to aid bedding in stubborn rings never done it myself have you any experiance?
Hi Horatio, no, I have never heard of it.
Head gasket leaking oil into cylinder.... a long long time since I've built one..
Since it had been apart before he got it, I'm now wondering something similar like a missing dowel on a head stud, some kind of top-end oil feed that's escaping into the cylinder from a stud hole.
probably oil soaked exhaust
I wish! The plug is getting oily, too, so the problem is further inside, sadly.
@@paulhenshaw4514 bugger.
I wonder if the rocker box oil drain hole is restricted?
Did it clear?
Sadly, it didn't.
Excellent🙈🏈
According to a previous comment you had the oil level too high last time
Someone else had the oil level too high - I lowered it, but it made no difference. It has been refilled with the correct amount of fresh oil with the top end rebuild, but still smoking.
@@paulhenshaw4514 I I remember rightly one measures the dipstick with the cap screwed down.
They put mix in the fuel by accident.
Sadly, no, that one was eliminated before the top end strip.
Another known problem with this bike was it used to break the camshaft. It happened to many I know
I had a CB125S years ago which did that.
has the engine got timed breathing
Hi Jeremy, it would appear not.
In my experience used rings in new bore has never been a success. Good luck.
The owner has sourced some new rings, which will be fitted for the next attempt ...
@@paulhenshaw4514 Should be good, if gapped correctly your troubles should be over with any luck. look forward to seeing the result. Stay lucky.