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1991 Honda CBR250RR MC22 vs 1994 Kawasaki ZXR250R (C4)

While the Honda CBR250RR MC22 is arguably the most well-known high revving 250cc four-cylinder motorbike of the 1990’s it’s not the only one, with Yamaha, Kawasaki, and Suzuki all producing their own versions of this configuration.

The Kawasaki ZX250R is likely the second most common 250cc four-cylinder bike from the 90’s in Australia, although comparatively far less common than the MC22 in Australia, with Suzuki’s FZR250 or Yamaha’s GSX-R250 being exceptionally rare. We’ve had the opportunity to ride a well sorted Kawasaki ZX250R and explore the differences between it and the MC22. Note that both bikes are around 30 years old, which can exacerbate and create differences between bikes that weren’t apparent when each bike was more youthful.

Handling

Straight off the bat, we noticed that the ZXR has a more aggressive riding position that not only increases weight over the front wheel, but also the speed at which our back and legs started becoming sore... We observed the ZXR to be more confidence inspiring in its handling, having better turn in and feeling more stable than the CBR.

Importantly, the ZXR250R has upside down rather than conventional front forks, and the bike we rode was sporting Dunlop Sportmax Alpha14 tyres compared to the CBR250RR’s less sporty Michelin Road 5 hoops. Having assisted the owner with carrying out some maintenance on the bike, we observed that the engine, cooling system and electrical system are all closer together and packaged slightly further forward in the chassis compared to the CBR250RR. This likely also contributes to the ZXR’s perceived superior handling, although the flipside is that it makes maintenance on the Kawa significantly more time consuming and difficult.

Of note, both bikes had recently had the oil in the front forks changed, but retained original (likely never serviced) rear shocks). When riding hard, owners of both bikes (us being one of them) have observed the rear suspension to be quite bouncy, likely attributable to the age of the suspension and lack of oil changes on the shocks. 

From an engineering standpoint the Kawasaki should, with its better mass centralisation, more aggressive riding position and superior front fork set up, handle better than the CBR. This is largely reflected in comparisons of these two bikes which you will find which others have done.

Engine performance

The MC22 has stronger top end than the ZXR250R. Both bikes have been dyno’d with the MC22 producing peak power of 41hp at the wheels and the Kawasaki producing 37hp at the wheels, on the same dyno.

The CBR also feels more responsive, while the ZXR250R feels a bit more docile. Where the MC22 has a noticeable increase in perceived power at 8, 10 and 12,000rpm, the Kawasaki is far more linear in its power delivery. Our MC22 has a louder exhaust and the gear driven cams produce a distinctive whine which may also contribute to the perception of a more significant power difference than there might actually be (i.e. greater than the 10% power difference suggests). That louder exhaust is also shorter than the stock exhaust and has reduced the bikes low end torque output slightly compared to the original exhaust, as measured on a dyno.

The CBR250RR has a taller rear tyre compared to what it should have (4.46%) which we compensated for using a rear sprocket with +3 teeth (55T = 5.76%). The effect of the tyre and the new sprocket is that, overall, the gearing is 1.3% shorter than standard. You can see our blog post talking about the difference that sprocket change made here.   

Given the differences in measurable rear wheel horsepower, and that the MC22 has had dyno tuning and leaner needles, whereas the ZXR250R has simply had a dyno run to measure its output, the notable difference in engine performance is likely attributable to the differences in these two particular bikes, rather than each model more broadly. We note that the claimed power and torque for each bike (when new) was identical, as was the RPM at which those figures were made: 45hp at 15,000RPM and 2.5kgm at 12,000RPM. From 1994 onwards, the peak power of both bikes dropped to 40hp, thanks to new regulations by the Japanese government at the time, although claimed torque marginally increased on both bikes.

The MC22 features a 19,000RPM redline, with the Kawasaki coming in at a slightly lower but similarly insane 18,000RPM. With both bikes making good power from 10,000RPM, this gives you a very broad RPM range to work within when you want to have fun, allowing you to stay in second or third gear while you wind out the engine. In reality, we find ourselves very rarely hitting 19,000RPM on the MC22 though, because in every gear except for first, peak rear wheel thrust occurs at between 13,000RPM (2nd gear) – 7,000RPM (6th gear).

Ownership experience

Each bike has been generally reliable, noting their age and the type of bikes they are: entry level performance machines that are likely to have copped significant mechanical abuse and less than optimal maintenance. Both owners have also spent reasonable money on preventative maintenance, reducing the possibility of unexpected failures.

The MC22 has gear driven cams, obviating the need for camshaft chain replacements, which can be expensive. However, the ZXR250RR sports a conventional timing chain setup which is not only an additional maintenance item (additional cost) but one that many people have skimped on doing over the years. That being said, the vast majority of motorbikes use timing chains and the issue of the chain being a maintenance item is the rule, whereas the CBR250RR’s gear driven cams are the exception. If you are buying a ZXR250R and there is no history of the chain having been replaced, you should budget for its replacement, noting their age and grey import history.

After a track day, the ZXR died on the way home. After some troubleshooting, this was due to an ignition lead coming loose from the ignition cap. Kawasaki have an unconventional (i.e. bad in our view) design whereby the ignition lead and the ignition cap are two separate parts, with the ignition lead sitting in the ignition cap, held in only by friction. The ignition lead is also hardwired into each of the two ignition coils, preventing replacement of the leads without also replacing the costly coils. Most ignition lead are removal from the coil, and include the ignition cap (which plugs into the spark plug) as one single part.

Kawasaki has an astounding array of new OEM parts which remain available. For instance, the fairing stickers, indicator housings, handlebar switch blocks and multitude other parts remain available which have long since been unavailable for the MC22. This situation is made slightly more baffling by virtue of the fact that the MC22 was produced and sold in what appears to be significantly larger volumes than the ZXR250R. There is still reasonable parts availability for bolts, washer, grommets and gaskets for the MC22, but many other parts are now discontinued. The thermostat for instance has long been discontinued, though we have sourced and fitted a Japanese alternative, which is available here.

 Having worked on both bikes, the MC22 is far easier to work on, with components being slightly more logically placed for access, with more space to work on each part. As we mentioned above, Kawasaki have placed everything tightly together, which can improve handling, but makes working on the bike quite fiddly. To replace the ZXR250R sparkplugs you need to remove the radiator. If you have a dead coil or regulator rectifier, you need to pull the ZXR250R fuel tank off. The  MC22 fairings are also easier to remove and re-place. For newer bikes the ease of access and overall difficulty of working on a bike is far less important where you are far more likely to be paying a mechanic to deal with that. However, with old and somewhat cheap bikes such as these, you are more likely to end up working on them yourself, where this characteristic becomes quite a bit more relevant to the rider.  

Styling

We love the aesthetics of the both the Honda CBR250RR MC22 and the Kawasaki ZXR250R C4. Both have very cool, distinctive headlight setups (common for the era but now rare), sold twin spare alloy frame, and the classic 90’s boxy tails. We like the gauge clusters of both bikes, with simple and clean gauges that place the tachometer at the centre, because engine speed is always going to be more impressive than vehicle speed on one of these machines…Of course, placing the tacho at the centre of the gauge cluster is a sporty design choice that many performance bikes and cars feature, and we love it. You’ll notice that the Kawasaki gauges are (in our opinion) a bit more interesting than the MC22’s, including a cross hair and a very retro triangle to indicate the redline, below where the numbers for the RPM sit.

No discussion about styling would be complete without mentioning the iconic vacuum cleaner hose air intake pipes on the Kawasaki. These are intended to funnel fresh air to the intake. Whether or not they provide a benefit or not is another question – they don’t act as an air ram set up like some modern Kawasaki’s. Similarly, although a bit more discrete, the MC22 has side intake runners which are superficially intended for the same purpose. However, once you unbolt one of the intakes on the MC22, you quickly realise any air which enters it is simply dumped at the side of the MC22’s airbox, which only features a front intake section, making it absolutely useless.

Fuel economy

Both bikes return between 4 – 5L / 100km depending on how they are ridden. Ridding the bike hard in the twisties will see closer to 5L/100km, which is very good. With 12L tanks, which translates to a real range of at least 200km, before wanting to fill-up. While not exceptionally fuel economy, particularly for a 250cc bike, it is nonetheless very good overall consumption for a four-cylinder, carburetted bike that puts out almost 200hp / L. Overall, this makes for quite an affordable city bike, which you can rev out without sacrificing too much economy. Shame the fuel tanks aren’t another couple of litres larger.

Practicality

Thanks to their boxy tail sections, both bikes feature storage under the pillion seat. The Kawasaki features a typically poultry amount of space which is just enough for some tools and the owner’s manual. On the other hand, the CBR250RR MC22 features a rather spacious storage area, which we have managed to fit a water bottle, tools, disc lock, and a spare t-shirt and pants into all at once. Compared to anything other than a cruiser or tourer, the MC22’s storage space is very useful and quite practical.

The trusty storage space of the Honda CBR250RR MC22

Conclusion

The MC22 is undoubtedly the more well known and more common bike. A large reason for that is likely down to the fact that it is simply a Honda, and one from what many view as their golden era.

 Both of these bikes are fantastic for what they are. When well sorted, they are more exciting and engaging bikes to ride hard than the equivalent small displacement sport bikes of today, which are dominated by single and parallel twin engines – the latter which does not feature a 270-degree crank (think MT-07). Which one is better suited to you will depend on what characteristics you prefer, as well as the availability of your desired model in your area.