OV9

@Jobbo I have just realised yours has the same engine as my Mountfield (see page1).

I am jealous of your variable speed control.

It does indeed - the GCVx170. I think I was expecting the 160 but Honda must have updated it in the last few years. My model was discontinued for 2022; the HRN replaces it but it’s a bit bling in comparison and has a partly plastic deck.

If you get bored, I’d be interested to know what RPM it is running at max speed? (The “giri” app seems to give reasonably reliable readings)

I’ll try it - the revs don’t seem to change with the speed though, not sure how the drive system works but it must be some sort of primitive CVT.

Interesting. Wasn’t expecting that. Probably not worth measuring rpm then tbh.

https://hondanews.com/en-US/power-equip ... ive-system

Quick google brings up this

jamcg wrote: Mon Apr 25, 2022 7:37 am https://hondanews.com/en-US/power-equip ... ive-system

Quick google brings up this

So it is - a cone system. Like the old Dafs

mik wrote: Mon Apr 25, 2022 7:29 am Interesting. Wasn’t expecting that. Probably not worth measuring rpm then tbh.

I did a measurement when I was mowing today - 2860rpm or so, I think. Giri seemed very keen on telling me it was twice that but it didn’t sound like over 5000rpm and I’m guessing it was picking up something going at twice the crank rpm; cams, perhaps?

Used the mulching function quite a bit today to try it out. It worked pretty well on the dryer grass but not so well on the thicker stuff at the back of the house. It definitely requires a slower drive speed; you get trails of clippings if you whizz around at top speed when mulching. So I don’t think it’s quicker than doing the lawn with the grass box even taking the regular emptying into account.

@jobbo - that sounds right enough then - mine is 2900rpm fixed according to the spec sheet.

I assume your speed control doesn’t change the blade speed, so I guess it makes sense that it’ll cut better at slower speeds.

I think the blade is geared directly to the crank so yes, it wouldn’t change with drive speed.

Does make me wonder whether I should try running it at a few hundred rpm more. Do you have a link to the governor spring changing guide?

Jobbo wrote: Sun May 08, 2022 6:39 pm
Does make me wonder whether I should try running it at a few hundred rpm more. Do you have a link to the governor spring changing guide?

Don’t think I ever saw one tbh - I can take some pics though. I bought a new governor spring so I can change back and forth (takes 30secs with a pair of pliers.

Do you just get an original spring and slacken it a little?

Tighten (ie shorten) it a smidge.

@Jobbo Some images.

With “Fast Road & Rally” spring fitted.


First tweak I did took it to about 3150rpm. Made a further tweak so this sets it to approx 3380rpm.



New spring part number if you want to be able to revert back to stock. In case it’s in for warranty repairs, or if you crash and the insurance send an engineer out to assesss it ….

my ///Mountfield that managed to break a bit on its first mow (requiring them to send a new bit out) has never missed a beat since in 5 years of hard labour. I gave the spring a little kink a few years back to give it a few extra rpms and I top up the oil about once a year, but that's all the attention it's had. I'm Impressed tbh.

My dad bought a Mountfield a few weeks ago as the Honda Izy is very much past its best but couldn’t get it to start.
https://www.costco.co.uk/Garden-Sheds- ... H/p/375968
Now I don’t know much about pushmowers but I don’t think much of Mountfield, you just never see professionals or contractors use them so I put them in that Ryobi category of good for at home but not much more (no offence intended to Mountfield or Ryobi owners!)

So anyway, this Mountfield, check everything, pull the starter, pull it 40 more times, kick it, swear at it. Pull out the spark plug tester and it has no spark
Just tell him to return it, I’m not impressed, I don’t think it’s a good mower. Aside from that it has other annoyances, I think it’s a 2 inch wider cut but it’s 2kg lighter than the old Honda, and much of this 2kg loss can be felt in the flimsy flexing handlebars - very thin sheet metal where it joins to the deck.

The cables are an inch too long so the levers flop all over the place and need to be moved 2 inches before they do anything. Non adjustable. The drive lever also works the opposite way but maybe that’s a Mountfield thing.

But by far this is the most moronic design

Compared to


And to top it off the Honda engine in it somehow produces less power than the 20 year old lump in the Izy.

I once physically threw a Mountfield into a wall as I got so frustrated that it wouldn’t start…

I went straight to the garden centre and bought a Toro which, 15 odd years later is still going strong.

I only went Mountfield as my dad has one that must be near 50 years old and still fires first time

Mito Man wrote: Fri Aug 09, 2024 8:05 pm
The cables are an inch too long so the levers flop all over the place and need to be moved 2 inches before they do anything. Non adjustable. The drive lever also works the opposite way but maybe that’s a Mountfield thing.

But by far this is the most moronic design

Compared to

His SP51H appears pretty similar to my SP53H apart from the smaller capacity (also) Honda engine, and the 53 has an adjuster on the drive cable so you can remove any slop at the lever.

What’s your moronic design issue? That the track is narrower at the front than the back, whereas that Izzy is narrower at the front than the back?

I’m fine with mine, but whilst I think it’s good value for the £270 I paid, I recognise that it’s not a premium heavy-duty machine.

No, the deck isn’t flush with the axle, so cutting alongside walls/raised borders would necessitate strimming whereas with the Honda you can just about get away without it.

Also the axles on the Honda are in line with each other, so you get a skinny line in the lawn to place your wheels on to get perfect straight lines on each return run. Not sure how it would work with the Mountfield, plus the issue with my first point would also not help.