stevew wrote: So the question to the assembled masses is;-
Can i ride it flat out all day (like my CG) and will it hold together at 9-10K revs ? Will be needing to do some big 300 mile days on it soon. Can i really rag it or will i have to molly coddle it ?

How tough are they? Honda has a good rep with their 125s generally.

Please don't tell me to get a bigger bike as i have been doing this sort of stuff for a good while on a CG125 and a C90. I like small bikes

That's a very interesting question that I've always wondered about. I suppose its possible to design an engine to have excellent longevity when used flat out all the time, but I guess that costs money, and the manufacturer always has to think about costs!
When I had a 125 I was commuting via a short stretch of 3 lane dual carriageway so it was flat out every day. I had no problems, though I didn't keep the scoot that long. With the relative lack of performance a small bike is always going to be thrashed.

The other issues is that thrashing anything is always going to increase fuel consumption, such that a bigger bike/scoot ridden more conservatively might have better fuel consumption than a thrashed small engine, and at faster speeds.

I really don't know, so I've always thought that leaving something in reserve, especially on longer trips, is a good idea. But the real answer is (sorry!), buy a bigger scoot!!!

my 3500 mile SH125 does 50/55 comfortably, maybe 60 - eventially - i do ride with a fair degree of mechanical sympathy - not on the stop... i dont think it will see this elusive 70 i here of - but then again i am not that svelt...

Most spec i can find from tests on the SH seem to say 60mph/100kph - Honda dont list a top speed...

XMax400Paul wrote:my 3500 mile SH125 does 50/55 comfortably, maybe 60 - eventially - i do ride with a fair degree of mechanical sympathy - not on the stop... i dont think it will see this elusive 70 i here of - but then again i am not that svelt...

Most spec i can find from tests on the SH seem to say 60mph/100kph - Honda dont list a top speed...

Ditto for my 33,000 mile SH125 (16k by me), 55mph indicated is top cruising speed and it seems to be OK to do that for 1-2 hours straight. I have Dr Pulley sliders fitted (can't remember weight) so it gets to speed well and despite being an early pre-FI (53 plate) does 90-100 mpg.

I think that's the phrase that says it all really - mechanical sympathy.
My TMax also does about 104 or 105 but I've not kept it there for long, just to "see what it'll do". It seems quite smooth and happy at that speed but I wouldn't dream of holding it there for long. I'd say cruising speed should be at least 15-20 mph below the manufacturers stated top speed, if you want your engine to last. And let the engine warm up before you wind open the throttle.
That, along with regular oil changes should ensure longevity.

I ran a Honda Swing 125 for 2 years & 11,000 miles and would still have it now except my commute jumped from an urban 17 mile round trip to a mainly dual carriageways 50 mile round trip so I choose a Forza 300.
The Swing is undoubtedly a great scooter but, with the engine only holding a litre of oil its needs changing every 2500 miles (8,000 on the Forza) . I did run the Swing for about 2 months doing a 50 mile round trip commute but found it struggled sitting at 60 mph and I didn't enjoy the battle with the lorries.
The Forza 300 sits comfortably at 65mph, is only a tad heavier than the Swing was, has more underseat capacity (although I could get my Badminton racket in the swing - cant do that with the Forza) and has a bit of power in reserve.
Had mine a year now and done 10500 miles on it and its averaging 84mpg. Swing used to give 99mpg but with the added Oil changes necessary there was very little in it.

You're right about the rev-limiter at 10,000 rpm BTW - at 65mph on the Forza its engine is sitting between 6500 & 7000 rpm.

Hope this helps with your decision.

I think if you concentrate on using a decent fully synthetic oil - and changing it as required - the engine will probably be fine.

Once run in;- a proper synthetic (Mobil 0w30 or 0w40 car oil will be fine - check the handbook for weights) will halt the engine wear and it should last for a very long time indeed.

You can leave s synthetic oil in for longer too - it just thickens very slightly, whereas regular or semi-synth tends to be blended multigrade which gets thinner and leave varnish all over the engine as it breaks down.

OK I'm getting a handle on this now.
First. It's no good comparing a de-rated 125 with a high powered bike. These little bikes are expected to run and run no matter how they are treated. The classic example of this is the little push rod engine in the CG. You can run that flat out for ever. Change the oil every 1000 miles and it will live with the abuse.
Why? Because it would be easy to make these engines deliver 20 bhp plus, especially with modern technology. Never the less we are restricted to 14.8 bhp by the learner laws. Therefore these engines are very under stressed.
Now as for 10k revs. Well most 600 fours rev their nuts off easily. Think the red line in the fast ones is around 14-15k. So these little 150cc pistons are running at 10k for a lot of their lives.
My hunch is that the S-wing's engine (13.5 bhp) will put up with this hard use.

I reckon Mr Honda knows this too.

BTW have always run fully synthetic 5 - 40 in all my bikes so I'll stick with that

plus on twist n go's they spend a lot of there life at a high and steady rpm in the 'sweet spot' some where between max power and max torque, and a little below the rev limiter by design, with the CVT rollers and spring taking care of the rest, acceleratation / road speed etc...
an understressed unit by design.

Currently using Castrol Fully Synth 10w30 in the SH, (3 more changes to go from the 4lt container) but will prolly go Halfords (made by Comma, who also make Castrol...) Fully Synth 5w40 after that... Cheaper especially with a trade card and 5lts - should get 6 changes / 15000 miles / 2 years!

I'll change at 2500 miles as recomended and in the old schedule - latest SH '13 on eSP engine schedule says 5000 mile oil change

with the 'lil SH125, you get quite a strong sense of when its happy, easing off when its feeling laboured, rather than pushing through for the sake of a few hundred yards up the hill or another 5 mph...

Steve W, You have got to look at your c90,and other,s how a little engine,thats last,s for all them 1,000, of miles.And still keeps going.

You could drive from London to Scotland and back easily on c90 or 125cc ect doing 55mph all the way their and back and even on a 50cc doing 30/40 mph but it would take ages and the numb arse would be hell ... that would be very painful.