Mini Bike tested: Replacement carburettors| Nathan Smith | Minibikes
I know people say you should not overload on carbs and have a healthy balanced diet, but here at br8 racing media we love carbs…the petrol vaporising type.
In the pitbike world the ‘go-to’ carb for plenty of years now has been the VM26 which is a Mikuni product. Widely used and seen as a pretty much necessity to go faster and keep up with the front guys and girls.
There are restrictions to what carb type you can use in the stock class of the British Championship, meaning that all flat slide carbs (apart from an Oko flat slide weirdly enough). Through trial and error people have tried different manufactures to find the perfect carb. A side note from this is you have to be careful when buying the carburetors as there are lots of fakes kicking around, and should only buy from reputable dealers who are experienced in the pit bike scene.
Anyway back on with the perfect carb, as you may know there are endless ways of setting carbs up , jetting, slides, needles, air filter, velocity stacks…the list goes on. Because its all about the small gains in any stock classes, companies and engine builders have now tried to find either new products, or make their current product better, and the next two examples that we have been lucky enough to test (before the world went in lockdown) certainly tick those individual boxes in the Parker racing Mikuni VM 26 and the NIBBI PE26 from Misano imports.
First of all the Parker Racing Mikuni VM 26, as you can see both carbs look simply amazing, but one slightly different to the other… the velocity stack! Parker has worked a tremendously long time on developing the carb to work along side two brand new stacks that have been expertly machined and then tested on the Dyno and also by his rider Ben Lord last season, here you have the final product.
We tested both of the different stacks with the carb that Parker racing generously allowed us to test we found them to have very different characteristics and feel. The shorter stack seemed to give you that little bit more bottom end punch than the normal VM26 out of the slower corners, which was great in the infield of the Ellough park circuit but didn’t seem to have much effect anywhere else on the circuit.
The longer stack was opposite, no gain on the slower corners from the lower part of the revs but certainly gave you a little more ‘Umph’ on the top end on the longer straights. All said and done this new design certainly made an improvement to the standard Mikuni VM26 and the jetting was not adjusted at all for the engine, each engine does differ slightly as we know. One thing though that was consistent with the standard Mikunis was that slightly lumpy feel from closed to maybe half throttle, a characteristic we have never been able to get rid of on the VM26 we have used in the past, this was no different.
The Nibbi PE26 is pretty new on the scene from Misano Moto imports and wow…..simply wow. Right out of the box the Nibbi certainly looks ultra cool as you can see by the pictures, and after slightly adjusting the jetting to a richer main jet (120) and a pilot jet (50) the carb came to life, and was simply fantastic. The main talking point for me should be that how smooth the power delivery is, no jerky bursts of power, just simply smooth as silk off the throttle.
Now when people have asked us about the carb we have been totally honest and said that we genuinely think there is more to come from these things in the sense that this was setup on track on complete feel, not on a dyno which could be beneficial. The carbs also was just ran as you can see it, no air filter and no velocity stack, so again with the addition of a stack could this be made even better? we certainly think so.
To sum all this up id say the new parker carb setup is defiantly better than the standard, and with more setup to your individual engine it could have even bigger gains than we experienced, and this is something Parker racing offer on their dyno setup. The new carb coatings also look ultra trick, and the machining gone into the collar and velocity stacks are second to none, hats off to Parker racing.
The Nibbi though is now my most precious belonging, well obviously apart from my child (wife wont read this so she can sit in 3rd place) I honestly think that this carb is a little gem of a find and the guys at Misano Moto imports must think they have really struck gold with this…well red and grey.
We would say as always try both of them if you can borrow from a friend at the track or even ride their bike with the two different options. The carbs were tested on a symoto yx140 (filter type engine) so people are aware of our setup.