Micro RS4 Vs M18

[Andy F]

i want one of these car but i dont now which one is better could anyone tell me the prices and any opinions on each Thanks

[Dynamite Arrows]

M18 M18!! lol

They can be quite equal in performance, but at our club a standard Micro RS4 has to be driven out of it's skin to keep up with the M18, drivers being equal. However, this is not the case at other clubs up and down the UK, as I'm increasingly told that the Micro RS4 CAN compete with the M18, especially when the radio is mounted nice and low (I can understand this) or when the Micro RS4 is made rear wheel drive only, as Lewis has done.

One plus point of the Micro RS4 which should never be overlooked ,is that it can take standard size radio gear - always a plus point for the beginner.

The M18 must have a micro servo, and to be honest pretty small electronics all round. The Xray power pack does all this, apart from a receiver and transmitter. It is possible to put a slightly larger than micro size ESC on top of the servo, but I prefer to have everything low down. Plus the space on top of the servo isn't that great as it's only a micro servo. A fairly large ESC, the Novak Hammer Pro will fit in the Micro RS4 but in an M18 - no way - only on a roof rack or in a trailer ;D

I like the M18 because it's fast, modern and I love the rear independent suspension that makes it quick through the twisty sections - the big plus is that it is so easy to drive fast.

I don't think prices are allowed on hear, but one thing to note is that the HPI Micro RS4 kit comes with a motor and the Xray M18 kit alone does not. My only qualm with the M18 is that it's long wheelbase which means my 140mm HPI New Beetle bodyshell won't fit :'( LOL

[Charles King]

shaft drive too!!!

[Barry_Hughes]

shaft drive too!!!


So What!!!!!!!!!!!!!
Belt Drive is actually as good if not better.

What is more important is that the M18 has full independent suspension.
With an after market chassis the RS4 is as good as an M18.

[Charles King]

a lot of people say that shaft drive creates less friction (personally i run belts) and i must admit the m18 has a very free drive train!!

[Barry_Hughes]

This has been discussed in the touring car thread, both forms of drive have their advantages and disadvantages. Shaft is more efficent with no load, belt more efficent under load, what is your car doing most of the time?

[Dynamite Arrows]

Quote: So What!!!!!!!!!!!!!
Belt Drive is actually as good if not better.

What is more important is that the M18 has full independent suspension.

With an after market chassis the RS4 is as good as an M18.

I wouldn't have an M18, if I believed that! As it said in a well known American R/C car magazine. If you're thinking of designing a 1/18 Micro - shelve it, nothing touches the M18. I think it must be drivers - 3 laps between the M18 and Micro RS4 at our club, 1 lap at best - the corners are where it matters and a standard RS4 is nowhere. If we only have one M18 racing and the rest are Micro RS4's then there is no race, when we have two M18's there are two races , Xray and HPI in one heat on a totally different pace.

Admittedly we have no DIY enthusiasts to modify their RS4's but I still think it needs the independent suspension all round.

Why are belts as good if not better, when they gather debris (if it's there) and the main reason they are less efficient is that the main thing they want to do is pull the two pulleys together, thet's the only way drive is obtained - through friction. Shaft drive does not do this, you can take the power off down the straight and free wheel under the stage and into the infield at our club 5 to 10 metres.

I like the Micro RS4 and all I can say is, if anyone has a fully modded RS4 and is within striking distance of our club, come and show me what they can do.

At least motors last about four times longer in the Micro RS4 than the M18, but the extra cost is worth is for all the rubber smoking grunt that the car gives - it's lower too! LOL It's so much more exciting to drive than the MRS4!

The argument between shaft and belt might be quite equal at times on the track, but it's simple maths & physics why shaft and gears are better than belts and pulleys.

I'm not going to argue with TTech, Associated, Yokomo, HPI possibly Xray and Team Losi's CAD systems - they've got the cash - we buy the cars!? - surely they are right in their research & findings??!? ::)

[DA_cookie_monstA]

Re: Shaft and Belt, which one is best, well, they do the same job in different ways, yes, belt drives try to pull the pulleys together, but then on a shaft drive, it tries to push the diff outwards, that is why is has to be shimmed up against the pinion, it also has to trasnfer rotation through 90' at either end.

This argument over which is best really is stupid in my opinion, they both have there advantages and disadvantages, the only time a transmission becomes really free is when you have a direct drive like in 1/12th.

If there WAS such a big advantage over one to the other, then they would all use the same system, have you ever thought that the reason behind the one system to the other, was a marketting ploy?? Do you REALLY think a single belt is better than a double belt?? or a shaft, I don't.

When it comes down to it, any drivtrain from a top company is excellent.

[Dynamite Arrows]

I think if Xray and Team Losi move onto shaft, then belts could be joining chain drive in the great transmission heap in the sky.

But for the company in Northamptonshire..

hey, it's a marketing ploy that works! ;D

I can't see a manufacturer of a shaft drive system saying, 'hey we we're wrong, someone pressed the wrong button, belts are better. I just love direct shaft drive, it brings the car to live in an instant (before you hit the power, some reviewers have often noted)

Belts will be around for a while yet, but for those that don't move on, life could be tough sales and results wise possibly -

The current world champions Tamiya seem to be getting results with their belt system, but even they have the Evo III in reserve or the much rumoured Evo IV

Going from an SST to a TC3 when they were released and going from the Micro RS4 to the M18 last year, showed me it is not a marketing ploy at all - just hit the button in the final and leave the rest, at least for the first few seconds - it's like Renault's F1 launch control - so much quicker off the line, back of the grid means you have to be quick with the steering to avoid piling into all those cars ahead! :D

I quite like the M18, I'm not going to talk it down when I have one and I love it to bits. We all have different opinions, but now the shaft drive transmission has (at last) been accepted, I don't think many of those manufacturers would return to belts. I also don't think that shaft drive drives the diffs apart or away from the shaft, they follow the path they are on. Lay a diff gear on it's side and hand drive it with a prop and it will turn where it is - try to do this with a belt and diff pulley on its side and you will be playing catch up trying to pull the belt away from the pulley to make it drive at all. The shaft will drive forever, the belt will never drive without tension in the system - the pulley needs to be fixed so that tension can be placed on the belt. Shaft drive doesn't do this, and a crown wheel will never wander off on it's own of it's own accord, it's being turned in one placed and will turn in a perfect circle forever with less resistance than the belt.


looking at the two systems in the car on a side view -

The belt wants to bring the pulleys together

The power from the shaft drive pinions on the end of the shaft are sending power either upwards or downwards - not outwards! I know what you mean, and I see your thinking - but the crown wheels are not being forced apart at all, merely to travel as fast as they can on a path, matching the prop. pinion speed.


Don't ask me why belts still win, I really think they are good drivers making the difference on the sticks, plus a near perfect set up with the car (practice at the track helps too!)

Whether the single belt is better than a double belt, that's tricky ??? Losi have shown that the single belts can skip under braking so ??, plus gigantic diff pulleys ! it still wins yes - good drivers IMO

The M18 transmission is really free on a bench, when a Micro RS4 is not - but results on the track count. I still think the M18 has it by a whisker or maybe the whole cat.

Hopefully the BRCA will be homologating the 1/18 cars soon, then we can have some meetings up and down the land to see how all the cars (inc. non HPI / Xray ) perform alongside each other.

Don't ask me to try and beat the Micro RS4 guys at Barry's club, they're all probably better drivers ;) LOL

don't forget it's just for fun! it's only toy cars at the end of the day! ;D

[DA_cookie_monstA]

Off Road, I could possibly agree their, but onroad, I think the two types of system are too evenly matched, but shaft drive I think in the end is easier to make than belt drive to a certain extent, with making a simple moulded chassis compared to the Losi effort, but that is it really.

My twin belt drive still spinds the wheels on the line, so it reacts quicke enough. So, I guess whilst makers still get good results with belts, there will always be too camps.

Plus I think for some, it is a marketing ploy and stops people just upgrading parts.. ;D

[Michaella Webster]

Lewis Taylor - On the Girl's Computer!!!

i have to admit, when i took the front diff and the drive belt out of my RS4 it did make it go faster, but then we are talking about a bit of an iffy belt drive anyway on the RS4 (and a tiny lille motor!), i don't like the path it takes through the car.. however in 1/10th onroad i really don't think it makes much of a difference!

I own a belt drive touring car and the drivetrain is very free, both on the bench and on the track.. it may not spin on for the same amount of time on the 'bench' as a shaft but.. no load roll-on time is no indication of the free-ness of the drivetrain under load.

on a shaft drive car you have the friction between the pinion and crown gears in the front and rear gearboxs, in a belt drive car the source of friction is the pinching affect of the belts on the pullys. who is to say which one is greater.

anyway.. on a large open circuit the RS4 can beat the M18 if you take the belt out because of the striaght line speed, on a tight circuit i don't know, i have not run it against M18s on tight circuits as yet in 2wd.. so i don't know!

[Doughty]

my view on this is that on flat carpet, direct drive pan cars will beat a touring car hands down.

the HPI is quite close to a pan car from what I have seen. the M18 is a scaled down touring car.

you only have to compare 12th circuit to 10th touring. 12th have less batteries, have to run for 3minutes longer and still get faster lap times!!

the shaft vs belt argument may be one thing.

but isn't the HPI direct drive? (to the rear wheels) and then belt from rear wheels to front?

[Dynamite Arrows]

Yes Chris it's direct drive, I still haven't tried the RS4 rear wheel drive only, I'd like to try it - like Lewis I'm not a great fan of the belt's route, a saddle pack battery with the belt down the middle would be good to try, but that means making new bulkheads front and rear (aargh). I'm sure there's a car somewhere like this, probably in the USA.

The RWD RS4 should be good on less twisty bends, we usually have one or two 180 degree bends so it would be interesting to see how it goes. It will rocket down the straight, that's for sure!

Need those 2.5 degree toe links for my M18, or maybe I'll make my own 1 or 0 degree ones, the straight is defintely one area where the HPI can match the M18!

I agree, RWD pan cars are way quicker than tourers and have been for years. Interestingly - the 4WD 1/12 cars that Hirobo and Kyosho tried in the 1980's were in the same layout as the Micro RS4 (but with a solid driveshaft arrangement)

The M18 can be a bit deceiving though, it has loads of upward travel, a very thin chassis and runs lower than the Micro RS4 (especially at the back, due to the independent suspension), there's little gap between the track and the chassis underside, but of course the transmission is totally different to a pan car.

The main thing for me as a driver is, the car is so much easier to drive flat out than the MRS4, on foams the standard MRS4 can be likened to stunt driving as it's forever loading up the outside wheels or right up on two wheels.

I will have to try the rear wheel drive Micro RS4, I'm running away with my series at the moment and need some kind of handicap (or not?) if it takes the bends, maybe it's plenty quick enough. But as I said, a long time ago, by doing this, the Micro RS4 resembles the ready to run GV Models Mini - R car - not much dearer ready to run than the current HPI kit price, that scares me a bit - that a car like that can beat a much more expensive package.

Anyone ever seen a GV Mini-R running? ???

(It's a Subaru Impreza with flourescent yellow wheels) the rear end is a dead ringer for the MRS4 without a belt, it must be just as quick in a straight line!

[Dynamite Arrows]

The belt's off my RS4, so I'll see how it compares tomorrow evening!

[Michaella Webster]

excellent... have you taken the shafts and the diff out as well?? what tyres are you running it on??

i am using 1/12th circuit tyres mounted on the standard rims, UFRA SE mediums to be precise.. less than £2 for a pair and they do all four wheels.. i run the backs full width and the fronts half width to get a ballance.. i found this out by acident.. messed the fronts up while truing them down!!

how long do the motors last, my car is starting to feel a little flat, do the cells go off quickly??

Edit 0- This is Lewis by the way.. on my girl's computer

[Dynamite Arrows]

Still learning about these two wheelers!, I didn't take the front diff or drive shafts out. Tried it with too grippy tyres (oversteer) and not enough (understeer). I will persevere with the car, though! I need some in between, but if I take out the front diff and driveshafts, maybe it will make it lighter and less grippy with the grippy tyres! (The grippy tyres are the HPI Carpet rears on the front ::), will I ever learn?!)

I struggled a little and then when I reverted to my M18, the HPI Motor was on it's last legs (Micro Modified) but this is my old motor from a long time ago, when it goes, it goes! the brush disappears and the plate wears to two prongs touching the comm. arc tastic! (and slow)

My friend won, and I was beaten by dad - would have done better with my 'tricky to drive' RS4! - I'll get the diff and driveshafts out for next week - my Xray team mate will be away, so I can play with HPI a bit.

I knew all this , remove the diff etc. from ages ago , but left it to my dad to do - he's none too hot on the idea of 2WD!


I have no idea how long the Mabuchi motors last, they will go 'soft' I guess, but when they die altogether I've no idea?!

The HPI Micro Modified motor lasts about 40 runs in the M18, a lot longer in the Micro RS4, that's for sure.

My mate is not running the Orion Core motor in the M18 at a high ratio and it seems happy and fine, so I'm going to try that sometime in mine.

next week, we'll see how I go with the RS4 (probably need the UFRA tyres )

[R@llyman]

What is heavier? Micro RS4 or m18

[Dynamite Arrows]

I think they are similar, possibly the Micro RS4 is slightly heavier?

I have both cars, but as they have different radio equipment in there, it's not really a fair test.

The servo in the M18 is micro sized so this is lighter than the servo in the Micro RS4. My ESC & servo are much smaller and lighter than the ones in my Micro RS4.

I think the bare rolling chassis are quite similar, possibly only 20g between them. :confused:

[Genem]

doesn't matter. I think the m18 is a no-contest winner.

[barnettgs]

I have been looking at both cars for a while and I think I would go for HPI Micro RS4. It is not that Micro is a better car but from what I have realised, despite both are similar sized, they are designed for drivers of very different needs.

For example, with HPI Micro, it is ideal for beginners and experienced RC users alike who want the minimum fuss as possible because it uses AA recharagable batteries & charger so it can be purchased cheaply everywhere and also best of all, you can fit any small sized ESC (doesn't have to be micro) plus normal sized servo and receiver so the budget is minimum for anyone and is great way of setting up new racing class without scaring first timers off!

On M18, I still think it's great car, but you need to have micro-everything there apart from the motor therefore xray micro package needed to be purchased and again, you need to buy a fast charger for battery pack. Again, you might want another battery pack so cost can add up It's fine for anyone who already owns a 1/10th electric kit, has charger but for those without charger or RC electric, it's a different situation.

If I have a friend who never been involved in RC so I would tell him to buy micro as I don't want to pressure him into buying expensive charger, batteries etc!

It is simply all because shaft drive is in centre of chassis so it created a space problem while Micro on other hand, has belt drive on right side, allowing more room for bigger equipment.

Other thing is, you cannot put in a modified motor to use with xray's 180 ESC (from mico package) so you need to buy a xray's 380(?) ESC but again, it's forward & braking only so best kept for racing at club, not for home.

So overall, both are great cars but I should put it that way, both are fun. It's all depends on users' needs that what matter most without hurting their pockets! RC hobby is all about the fun.

I think it's pointless to discuss how great one is at handling speed, blah, blah etc but believe me, if I have a local club racing based only on same crap car, no matter what makes, I would buy the same just to get in to race with them! ;)

[Dynamite Arrows]

Don't really understand your logic and why you would choose derogatory terms for any car, they are all so much easier to build and drive these days than say 15-20 years ago.

One thing I'm a bit iffy on 'home use' for a Micro, in a small area everything will get really hot and outside I'm sure a Micro will fit down the gaps in a grate cover.

I think a four cell HPI Micro running Alkaline Duracell batteries should be pretty good, but as you say it won't out corner an M18 (I'm sure it says that reading between the lines )

The reason the HPI has more room for radio is that it places the receiver and ESC on the top deck, over the top of the servo and battery making a high C of G. M18 uses a wider chassis to get everything nice and low.

Two reasons I would vote for the Micro RS4 for the beginner (having run both cars) we've had lots of problems with servo gears in the M18 (using non Xray servos) plus it seems the M18 can expire a 180 motor in three months (racing weekly) where as the Micro RS4 is much easier on the motor, lasting approx a year.

M18 though every time until HPI release their shaft drive Micro, then there will be some competition ! :eek: