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With petrol still going up, what kits are producing the best fuel economy in MPG?

TBH, I don't think economy has much to do with kits themselves. It's all about the set up. It's more to do with the carb' size and the jetting, the state of tune, the exhaust and its type, the scooter itself (ie: S1/2 or S3/GP), the weather, the size of the rider and the way that the rider, rides!

Rich'

GExS wrote:With petrol still going up, what kits are producing the best fuel economy in MPG?

Standard

Solid Air wrote:

GExS wrote:With petrol still going up, what kits are producing the best fuel economy in MPG?

Standard

Agreed!

Rich Oswald wrote:

Solid Air wrote:

GExS wrote:With petrol still going up, what kits are producing the best fuel economy in MPG?

Standard

Agreed!

But keeping it standard is a completely different issue isn't it Rich?! I'm not sure it's possible for most riders to do that, I know I can't! Sod the MPG

Weather conditions are a big factor. Get a strong headwind or steep hills and your mpg can plummit, especially if you're struggling with gearing. With my Avanti, Franspeed Race and 35mm Mikuni, I'm happy if I get 40mpg.....which I do sometimes but it cango to less than 30 if heavy on throttle or bad headwind

Agreed![/quote]

But keeping it standard is a completely different issue isn't it Rich?! I'm not sure it's possible for most riders to do that, I know I can't! Sod the MPG [/quote]

Me neither, fun factor is far better than mpg.

I’ve heard GT kits with the reed valves can do economical.

I use a Suzuki 185 conversion with a 60x115 crank, 22 Jetex and standard exhaust. It’s very economical and quite quick.

My RT195 (198 or whatever it is a 60 crank gives you) gave me around 13.5 miles/litre going to Moffat and back. Not going too mad (Mostly. Gave it a good blat on A6 back to Penrith) as new rings, clutch spider, plates, which had yet to have a good run.

My RT235 with a reed gave about 13 miles per litre going to Moffat and back, Mixed riding, Motorway and A & B roads. I'm quite happy with that.


£2 a litre for E5 on the M6 near Carlisle, I'm not quite happy with that!

GExS wrote:I’ve heard GT kits with the reed valves can do economical.

I use a Suzuki 185 conversion with a 60x115 crank, 22 Jetex and standard exhaust. It’s very economical and quite quick.

Yes the GT with a smallish carb is economical and a good little kit BUT if you're thinking of changing to that from what you've got I wouldn't bother. They are very similar and what you'd pay out wouldn't reward you with performance or mpg to justify it.

My avanti with a phbh 30mm and an exbox st gives me about 80 miles to the tank. Don’t really care of the cost of fuel because the joy of riding the scoot far outweighs the monetary cost.

Significant factors that I believe constructive to fuel economy:

With any static ignition, don't go 'safe' & then some. Even on a tuned engine, as long as premium fuels are used, it's unlikely timing needs to be backed off more than to 19°BTDC IMO.

A good oil that can work @ 2% can prove economical, though this subject has been discussed endlessly

An adequate, 'uphill' remote air filter that completely obviates the issue of saturation of the element (& your left loon pants leg) is a no-brainer. Unfortunately, even modified OEM filter set-ups will stifle any engine's potential even with moderate levels of tune beyond just the 'bolt on kit' scenario, which inevitably involves a venturi size of above 26 mm IMO....

I have run my GT186 with three different exhausts and two different carbs over the last 9 years, or so. I had the barrel modestly tuned a couple of years back when it needed a rebore.

I don’t religiously monitor miles per litre but, having reduced the size of the carb recently, I did a couple of weeks ago.

Anyway, in a former set up of a PHBH30, remote filter, non tuned and early MB/bgm Clubman, it did about 14 miles to the litre on a run to Kelso about 6 or 7 years ago.

Now, with a smaller carb, a Mikuni TM24, remote filter, a bit of tuning and an exhaust that revs higher, an Avanti Xbox, it only produced 12.5 miles to the litre on a recent run of 170 miles.

I know this isn’t a great comparison, given the state of tune and exhaust were changed as well as the carb, but it does perhaps show that a smaller carburettor doesn’t necessarily bring with it substantially better fuel consumption.

I’ve debated putting my 25mm PHBL on my Reed valve iron 225 to see if I can squeeze some more MPG. But with the 30mm Dellorto it’s set up near perfect and I don’t want to faff about with it when I’m leaving for France/Belgium next week.

A stock 125 or 150 will be best on petrol , scootering as it used to be !! G

Targa is very good on fuel last weekend on 275r getting about 14 miles per litre at rough calculation