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CB500X Miles Per Gallon
Blog Date - 23 February 2018
Some say he's so tight he only ever breathes in. Some say he uses a candle to heat the house - if it's really cold he might even light it. We've heard he looks under the bed in the morning to make sure he's not lost any sleep. All we know is he's called...Ren - The Ed.
I'm not tight. I'm prudent.
I've been to see pops this week. He lives daaaaan on the saaaaaf coast which means a 270 mile trip each way.
Back in May 2012 I went to see him on my Fazer 600. On that southbound journey I kept to the left lane and followed the trucks. With around 235 miles of motorway and 35 miles of flowing A roads I achieved a staggering 79.5 mpg. I did it without filling up. I thought that was rather impressive for a 95bhp 600 four.
Sharon gets rather tired of my slow pace. Personally now I've covered a lot of motorway miles on the 125 and many more on larger machines I find keeping the speed down to be rather calming. I used to be hanging on to the bars at 70(+)mph, dodging slow lorries and fast executive Germanic cars, stressing over my licence and getting very tired very quickly.
Now I serenely waft along behind a suitable truck, relaxing in the seat with a gentle breeze upon me, casually noticing my surroundings, hearing my thoughts and awaiting the arrival of my next turn-off. Oddly, counter-intuitively I find I can easily cover the miles that once troubled me. If I'm a little stiff I wriggle, if I'm tired I stop. And still my journey takes the same amount of time.
Life can't be rushed on a 125.
So this week I did the same experiment. This time on the already more frugal CB500X. The journey started badly with a local road being closed requiring a detour through Wigan at rush hour. The M6 from junction 20 to junction 15 is presently covered in road works that brought on almost 30 miles of stop start traffic and 15mph filtering. Luckily the rest of the trip was, erm, average.
And the mpg? 97. Both the average mpg on the computer and my mathematical calculations agree, give or take the decimal points.
Whoop whoop!
There's a part of me that's impressed. And a part of me that may be just *slightly* disappointed.
I'm impressed because it goes to show that a motorcycle capable of acceptable levels of performance can achieve almost 100mpg if ridden like Scrooge. It's a 25% improvement on the Fazer and a considerable improvement on the NTV600 Revere I used to own. Here's to modern fuel injection systems.
The 'owd NTV 600 Revere was a great bike, but it liked a drink.
But then... The Fazer used to return around 55mpg on the regular urban cycle whereas the CB500X returns 80mpg. If we were to use a sliding scale then if the Fazer can be persuaded up to 80mpg with careful use then the 500 might achieve as much as 116mpg.
Science doesn't work like that though. Even with the most precise fuelling the fact remains it takes a certain amount of energy to move a motorcycle and rider over a certain distance at a certain speed. While the 500's fuelling may be better I figure the engine's thermal efficiency would only be fractionally better than the 4 pot Fazer.
Still I am pleased. On the return leg I indulged myself with a few squirts up to the legal limit then I re-learnt another advantage of keeping the speed down. Warmth. It was bitterly cold on Thursday and after a few miles of 70mph the cold started to really bite hard. I resumed my normal position behind a truck. The cold reduced from concentration-busting shivers to merely bloody cold.
If you've got an interesting motorcycle related article then maybe we could publish here on Bikes And Travels. Contact ren@bikesandtravels.co.uk
Reader's Comments
Pocketpete said :-
Not managed to get my 500 over 75mpg.....
I really must be a fat git.
24/02/2018 15:56:48 UTC
Ren - The Ed said :-
I don't think it's your greater ability to warp the space-time continuum Pocketpete. I expect it will be the traffic you encounter and the kind of riding you do.
Set your dash thingy to mpg. You will see several occasions where it will read "99.9" (because I assume the LCD display doesn't have an extra digit to show over 100). You soon learn what antics drink fuel and those which merely sip it.
That said - concentrate on the road and not the numbers. I learned this almost the hard way.
26/02/2018 08:55:03 UTC
Pocketpete said :-
Hmm driving to save fuel.
Why would I do that. Come on ren us well off ish people wouldn't think of saving the planet or ozone layer. Let alone a bit of unleaded.
Now where's the Bolivian coffee we ordered from that none fair trade plantation...... in the cupboard with the rare Russian caviar....
27/02/2018 08:01:55 UTC
Ren - The Ed said :-
It's because I'm incredibly tight Pete.
27/02/2018 14:50:33 UTC
Latchy said :-
Only here once, I prefer smiles per gallon way hay!
12/03/2018 20:57:29 UTC
George said :-
That's really interesting to find that the CB500X can manage that.
I've got a CB125F which is now hitting 130 mpg on the commute (mixture of dual carriageway and the Leeds ring-road). It's been improving with each tank though, so I'm hoping the engine is still bedding itself in as I approach 5k on the clock.
Anyways, am moving somewhere rather more remote in the coming year, so if the CB125F doesn't like the rough gravel track leading to the house I was eyeing up a frugal dual-sport that I can still service myself :) CB500X or CRF250L/Rally were topping the list...
Cheers.
29/05/2018 19:34:29 UTC
Ren - The Ed said :-
Hi George. When it comes to fuel economy I'd expect the CRF250 to be better than the CB500X, but not by a huge margin. When it comes to self servicing I'd say the 250 will be easier here too. If it's purely for commuting then the 250 in my opinion is the better bike.
The 500 is a great bike though. It offers a little more performance for not a lot less economy.
30/05/2018 05:12:29 UTC
George said :-
Hi Ren,
Thanks for the response, having previously had an old ZZR600 and downsized to the 125, I must say I'm preferring the less popular quiet-and-sedate style of motorcycling now. That and not having to remove half a dozen fairing panels to access anything.
It'll be for a mixture of stuff - longer trips to visit folks & shorter adventures to explore. Am used to packing light from bicycle touring.
This blog's been a great read, been trawling through the back catalogue :)
30/05/2018 11:13:21 UTC
Ren - The Ed said :-
Yeah erm... doing the tappets on the 500 is easy. GETTING to the tappets is a bleeding nightmare. I've not done the 250 tappets though I'd expect getting to them is easier.
Glad you're enjoying the blog, it's been 15 years in the making :-)
30/05/2018 17:37:56 UTC
Joe Crennan said :-
A cb500x gets better mpg than a crf250 or my cbr300.
24/09/2020 21:17:47 UTC
Ren - The Ed¹ said :-
It all depends on how you're riding Joe Crennan. I think if you were to ride either of your bikes as gently and as carefully as I usually do I think 100mpg wouldn't be out of the question. Equally I can push the MPG right down if I'm hard on the throttle. That being said the 500 seems to be a frugal motor.
25/09/2020 09:16:30 UTC
Marv said :-
Think I've commented on this somewhere here before. Generally with my bikes, over the course of a tank:
2017 CB500X- 85-95MPG
2019 CRF250 Rally - 95-105MPG
2012 CBF125 - 140-150MPG
I think the CB500X motor is remarkably frugal, given the weight of the bike (Probably helps that I'm a skinny git too). But then I guess it does run lean for emissions (Honda didn't have to make any changes to make it Euro5 compliant) and it's in a low state of tune to keep it A2 compliant.
25/09/2020 10:00:13 UTC
Ian Soady said :-
I rarely check mpg on my bikes. What I have found however that I almost always get around 55 mpg - on bikes varying from a 2004 955i Triumph Tiger to a 1952 Norton ES2. I suspect it's because I tend to ride in the same manner regardless of what I'm on......
25/09/2020 11:46:57 UTC
Ren - The Ed¹ said :-
I too found most of my "mid range" motorcycles before the 500 would give roughly 55 mpg. I reckon Marv is right though. A 500 twin motor is easily capable of 60 maybe 70 bhp so the A2 "detune" must play a significant role in Honda being able to focus on economy rather than performance. What's also impressive is the NC750 models which weigh more than the 500 range and yet still achieve similar economy.
For years motorcycle development was "performance performance power power", leading to this typical sort of 55mpg figure. My Astra 1.3 diesel regularly returns 65 mpg and while not as quick as a bike that motor is dragging over a ton of metal around. I understand for most westerners motorcycles are a toy, a plaything so fuel economy isn't a major factor.
26/09/2020 09:30:48 UTC
Martin Mac said :-
Whatever happened to U.S. military KLR650 diesel ?! Supposed to be intergalactic mpg from them, plus loads of torque of course, would've loved one. Would love an electric bike too but stupid money to buy them. Worst bike mpg wise was the FZ1 courtesy bike I had for 3 weeks, after being knocked off my my xf650 freezing, 25mpg average, I caned it, a LOT. Stupid fast, which is why I never own such bikes, like a kid in an mph/rpm shop, you WILL partake in one or both eventually!!
31/07/2021 01:08:06 UTC
Ren - The Ed¹ said :-
Martin Mac - Yes WHY!!! Imagine a 650 diesel adventure bike. OK so it's not going to be as fast as a GS1250 (or a 500 single for that matter) and heavier than a ship's anchor BUT! Thump thump thumping along the motorway at 70mph sipping diesel (or any old chip shop fat) at 3,000 rpm and 100+ mpg. Enough torque to pull a caravan.
Agree too with the leccy bikes. You may know my 125 is on it's last legs and a 125 equivalent leccy bike would be ideal. I'd keep the 500 for longer trips but an 80-100 mile range would cover all my commuting and socialising needs perfectly fine. However a 125 equivalent runs around £4,500 and I could buy 3 Chinese 125's for that much and still have change. I hope the range/charge speed/prices improve with new tech and take-up, but for me we're not quite there yet.
"like a kid in an mph/rpm shop" - excellent comment. Power corrupts, and absolute power corrupts absolutely. While any motorcycle only goes as fast as you twist the throttle if you put temptation there how many of us are truly self controlled enough to not use it?
Hope the XF650 Freezing (Freewind) and you are both OK.
31/07/2021 09:01:03 UTC
Joe Crennan said :-
REN - the Ed
I concur.
my mpg acumen beyond any as I rarely need to brake, being able to outrun pace absolutely everyone in traffic (even at 64). But at same or faster pace CB500X seems better. It could be it has just the right amount of power at low revs whereas the smaller bikes need a bit more, but probably engine efficiency at these revs.
I can get 300 mpg (over several miles) on a 2021 cb125f @ 22 mph. Regularly 170 mpg thrashing it. I weigh 90 kg.
My new Ninja 7 hybrid averaged 84 mpg on a 5300 mile mostly Italian tour. Same as my cbr300 700 miles to Ireland via Scotland and my Chinese bike in the USA over 3000 miles (229cc Honda copy off road bike 21” 18” wheels)
11/07/2026 17:20:43 UTC
said :-
11/07/2026 17:20:59 UTC
Martin said :-
Wow Joe,
300 mpg from a CB125F, that is amazing though 20 mph would take a lot of self control. To still get 170 mpg while thrashing it is even better. In my experience you pretty much have to thrash an 11 hp 125 to keep up with traffic so to still return 170 mpg is brilliant. I am now actively looking for one though I think I will try to find a low mileage 21-24 bike rather than the later chinese built model. My old GS125 was supposed to give up to 120 mpg but as I usually thrashed it I only saw about 100 mpg, still good. An LS125R I had at the same time only gave about 85 mpg but was fun to ride and a lot faster than the GS.
16/07/2026 22:37:54 UTC
Martin said :-
Hi guys, just bought a CB125F on ebay. I did find a low mileage pre-chinese bike at a good price so picking it up on Monday. Looking forward to some ultra cheap biking. Interestingly the bike has heated grips which I am a bit concerned about, surely the alternator was never designed to cope with that plus lights and starting? As it is the older model at least it does not have auto stop/start!
24/07/2026 15:28:12 UTC
Upt'North ¹ said :-
Martin, if you know the make of grips check out the wattage, I would of thought they'd be between 30 to 40 watts on high. That shouldn't be a problem once the bike is running at decent revs. The parasitic drain will be practically nil. I've never personally used heated grips although sometimes wished I had.
Upt.
24/07/2026 16:44:04 UTC
Martin said :-
Thanks Upt,
I have never used heated grips either and suffered accordingly! It will be interesting to see how much difference they make. I will probably fit hand guards also as I think keeping the wind off should make a difference. Again not something I have previously tried but seems like a good idea. Pretty sure the grips are Oxford, I see they draw less than 4A so less than 48W. Now try to find the alternator output. I assume the lights are led so not much wattage there either. I think possibly the charge fault light would illuminate if the grips and lights exceeded the alternator output. This would likely be the case at low revs but should clear as the revs rise? I will have to experiment.
24/07/2026 22:27:39 UTC
Ian Soady¹ said :-
I think handguards (or even better handlebar muffs) actually work better than heated grips. The grips tend to make your palms hot and sweaty but the backs of your hands get frozen solid. When I was using a bike for commuting year tound - yes even when it rained (and snowed!) I used handguards and was happy with them. If I'd been regularly travelling 50 - 100 miles I'd probably have wanted both.
https://jsaccessories.co.uk/category/motorcycle-accessories/motorcycle-parts/han...
25/07/2026 12:24:27 UTC
ROD¹ said :-
I use handlebar muffs from around September through to May. I only use the heated grips in really cold weather and then only on the low heat settings.
The handlebar muffs have the added advantage of allowing you to use summer gloves all year round, and they also keep your hands dry in wet weather.
25/07/2026 15:50:13 UTC
nab301 said :-
Martin , Honda don't seem to list the output of the '21 on CB125F alternator but a google search suggests 190w output with approx 130w as the standard drain when running. Theoretically 50w grips should be ok but with only a 5a/h battery listed I'd imagine that other than on full throttle the battery may discharge . Also as that year model has a combined starter / alternator I'm not sure if overloading it could damage what might be an expensive replacement?
Nigel
25/07/2026 17:20:25 UTC
Martin said :-
Hi Gents, thanks for your helpful comments. Ian, I like the thought that handguards or muffs work better than heated grips as powering the grips must absorb engine power obviously. Like you I used a bike (GS125) to commute for seven years in all weathers though to be honest I usually took the car in bad weather when leaving the house. As I was a shift worker I reckoned I was far less likely to fall asleep on the way home from a night shift if I was on the bike! Thanks for the link. ROD, thanks for sharing your experience of muffs, something I have yet to try. Nab, thanks for finding out the alternator output, it does appear that powering the grips should be within the capability of the bike but as you say perhaps taking the power demand close to the limit of the alternator. As the bike has the heated grips already fitted I will not remove them but only use them as strictly necessary.
27/07/2026 20:30:57 UTC
Ren - The Ed¹ said :-
When you consider the CB125F's engine power output is 8 kilowatts (8,000 watts) then the drain of heated grips is negligible in terms of engine power. However - the more load you place on the charging system the sooner it will fail. My earlier CBF125 went through 3 alternator coils in 100,000 miles and that was without any serious additional drain on the system.
You're quite right - use the heated grips as little as possible which will minimalise the strain on the system.
Hand guards are effective - they won't leave your delicate pinkies toasty warm on a winter's ride but they help take the edge off. Muffs are more effective but a word to the wise - be VERY careful when buying and fitting. It's all too easy to have the muffs interfere with the operation of the levers, particularly when you get up to speed. The headwind can flatten the material onto the levers and you wouldn't believe how much effort is required to lift a wind-blown muff off a lever to operate it. Don't ask me how I know. Ensure a good space between the muff material and the lever - even at speed.
29/07/2026 08:17:36 UTC
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