Getting cheesed off now

[PaulD]

After sorting my carbs out I thought I would treat the old girl to fresh oil & filters all went well until on start up it started smoking like a good un? At first I thought I might have overfilled it slightly but after leaving it to settle for an hour the oil was half way up the sight glass. While I was having carb problems I noticed on one of the many test runs it was smoking when I pulled away from a stop but it seemed to clear up. It’s always smoked from cold but clears up quickly. As a desperate last thought I’m going to check the cam box breather tube isn’t twisted or kinked but after that it looks like I’ve got to strip the top end and check bores/pistons/rings etc. I’m a bit pissed off now as the bike was supposed to have had a new top end and cost me north of £7k with the deal I did on my old Kettle. Anyone got any ideas before I strip it or dump it in the canal near Fossie?

[pop-up]

In a previous post you found a discrepancy in cylinder pressures.Did you get to the bottom of this or now on the 'to-do' list.

[fossie]

Firstly smokes from cold then clears up.......valve stem seals! If the refurb was done with a cheaper gasket set. Say from Athena ( Italian ....not known for mechanical prowess.) the supplied valve stem seals are ok but need soaking in oil to soften them ....if not they swell unevenly to the valves.

Answer ...forget it mate...the smoke is behind you so not your issue! My S2 has been like it since I bought it 7 years ago....Switzerland , many jaunts on club meets adding to 10.000miles ....no loss in power. Just top up occasionally .
The 650 that was featured in Practical sportsbikes did 250000miles and when I sold it apart from a gummed up valve guide the motor was fine....ok so the valve was gummed up but come on 25x the milage you are going to do in a life time this was in a few years of constant use .
No as oddball said " stop with the negative waves".
If it was an le brit bike it wouldn't be seen as an issue ....just character!

[PaulD]

Well I understand what your saying but it does smoke more than my Suzuki kettle did and as you know that was bloody two stroke the problem is I’m a bit of a perfectionist and if it ain’t right it drives me nuts.
Weather permitting I’m going to take it out and to quote Mr Cleese ”give it a damm good thrashing” I’ve got the AA on speed dial so I mustn’t forget to take my phone with me
I’ll let you know how I get on.

[johnr]

use genuine suzuki valve stem seals, dont use cheap aftermarket ones and certainly dont use ape peerformance ones (only designed to last a season) but if the compression is down, then it sounds like a more serious issue

[PaulD]

Thanks for the replies fellers, I’m going to see if I can put up with it this season and then pull it down and sort the problem over the winter. I’m reluctant to give up on it because 1) I hate being beaten 2) I don’t like admitting I’ve been ripped off, the bike in my eyes at least looks stunning and obviously had a lot of money spent on it, just not on the engine obviously The main reason I bought it was so I had something to ride that I enjoyed while I concentrated on the resto on my T500 Suzuki.
At least it looks nice when it’s parked up

[johnr]

worth asking what oil you use? my old kat was run at first on fully synthetic (cos a mate in the trade gave it me free and i couldnt resist that price). it smoked and whilst it ran great, the blue haze really got on my wick after a while. then i tried going back to bog stock mineral, iirc i went to duckhams 10/40 mineral. smoking stopped immediately. modern synths are a miracle of automotive technical know how, but old bikes werent built with the super tight clearances of some modern tight watercooled missile, so i went back to old oil and my problem went. worth a try if youre running your aircooled motor on modern oil.

[PaulD]

Thanks John but I’m using Rock Oil 10/40 mineral as like you I found out that our old tech motors don’t like modern fully synthetic oils. My old kettle used to run alarmingly rough when run on synthetic two stroke oil even though there was no smoke. Changing back to good old mineral and she run a smooth as a very smooth thing in a smooth factory

[PaulD]

Well just back from my run out and after the initial couple of miles where she smoked like a good un the smoke screen stopped altogether? I only did a short run of 65 miles and even after stopping for a brew for 20mins there was no smoke even on start up I’m now at a complete loss to explain what’s going on? So apart from a carb rebalance she’s good to go and only time will tell if I can trust it on long journeys. Here’s a pic where I stopped for a brew and a break.

[johnr]

any freshly built motor will require a period of bedding in. perhaps you were too gentle on the throttle and glazed the bores when you innitially ran it in. i know the guys who raced big ujms back in the day would start a freshly built motor up and run it gently for an hour round the lanes, then take it for a good thrash, just making sure not to put it under heavy load for a couple of hours running. you might have literally thrashed it right, or, as scott in edinburgh calls it 'an italian service'
when i used to take the wifes little c90 step thru for its mot, i would absolutely paste it through the gears on the 15 mile ride to the mot guy i use, at the beginning of the run it would do about 45mph and be a bit wooly on the throttle, by the time i returned home it was fresh and crisp and revved cleanly all through the range and could now do just over 55mph, she was convinced that i had it serviced at the mot station because it ran better on my return, and to this day she doesnt accept that an engine needs a good pasting every so often to just clear it out.