KZ vs Honda Shifter Engines movie

There is no question that this is the end of the line for the Honda Stock Moto engine; it's been great for many years, but now, with introduction of both the Rok and KZ engines, the Honda is just outdated. Like many folks who are looking at the Shifter/KZ class, I also wonder about the difference in performance. I knew the gap was there, but difference surprised me.

[@billkingsbury4866]

Love this video! Very well done and informative!

[@beginagain8101]

Thanks Bill, it was lots of fun to shoot, I promise you!

[@brian.d.mobley]

Great camera work! Very interesting content!

[@danagibbons99]

Great info !! Thanks for the video !!

[@RKSiler]

Thanks Dana! I hope you are managing to get on track on a fairly regular basis these days...the weather here in North Texas has not been too kind in that regard lately...

[@donnywalker4691]

Great video guys fun times

[@RKSiler]

Thank you, Donny, I appreciate the kind words...we had a lot of fun filming this video, and when we can get everyone's schedules sorted out, we want to do a KZ vs Rok comparison that is similar to this video...obviously, the gap between the two engines is much closer. Thanks again!

[@guilianocipria5218]

How's it going young man i just slammed a new TM 10 Titan in my 2017 DR J90 shifter as well

[@truegret7778]

Great comparison. Question - is Jack "[edit] blipping the throttle" (or does his right foot spasm like mine when I am having extreme fun) through turn 7 (timestamp 04:10), and through 8-9? Or is the track just greasy and bumpy and we hear the tires grab-and-release over the bumps? Another question - are the classes "normalized" and the same region to region, track to track? It seemed to me, watching you race at NTK, there was a definite disadvantage in the Honda when running against KZ karts in the same class.

[@RKSiler]

Jack is blipping the throttle for sure, could be a tool he is unconsciously using to search for grip...quite a few drivers do this, and of course, Ayrton Senna mastered the technique and a bunch of us have tried to emulate him. As far as normailzing the classes, the KZ carries a handicap of 30 pounds over the Honda, but the difference is not nearly enough. Not sure what it would be, but the KZ engine is just really strong. Same applies for the Rok, although it is not quite as powerful as the KZ.

[@Reuben_Mamelok]

The reason for Jack blipping the throttle is literally just so he can shift up, same as a lot of sequentials in cars, I wish there was more to it but there isn’t 😂

[@lanakimanatou]

KZ is a open motor approx. 50 hp vs. a Stock Honda approx. 42ish hp I know they don't race open Honda's anymore, but that would be a closer comparison. Open Honda's was pushing pretty close to 50hp

[@beginagain8101]

Thanks for watching this video! What we were really trying to do was say, "We know the KZ is way faster than the Honda, but how much faster and is it so different from the Honda that a driver new to shifters would have a tough time dealing with the engine?" What I have learned since then is that the real thing about the KZ is not about how you drive it but how you tune it. I now have a Rok Shifter and I pretty much have come up with a jet for the carb that works in 75% of the conditions that I run in; only on a really cold or really hot day to I need to change the jetting on that engine...the KZ is a much different beast, from what I am being told, you need to constantly change needles and jets to keep the engine tuned correctly. This is just from what I have heard, this is not from personal experience. I take it that you race with a KZ?

[@lanakimanatou]

I have several, :( Stock Honda, Mod Honda, 2 KZ. Great Video But I would not suggest an new driver to the sport jump in a shifter, I would point them towards a TAG. With the speeds a shifter, it's really dangerous having rookie shifter drivers on the track with you. @@beginagain8101

[@carlosishac8954]

Hi i have a kz2 praga it seems to be jerky in 1st and 2nd gear .tho when in power band from 3rd to 6 gear no problem. I have 165 jet coz winter. Any idea why im getting jerking in lower gear. Cheers from Sydney Australia.

[@RKSiler]

Hello Carlos, and thank you for watching "KZ vs Honda" and for your question-greetings from Dallas, Texas! I am now running the Rok Shifter engine, having moved from the Honda, but I am by no means an expert on these engines (yet). I sent your question to my buddy Jack from this video, and he and I agreed that the "jerking" you are feeling could be caused by running too low of a gear in a particular corner. That has happened to me on several occasions and there is no doubt that the "jerking and bucking" can be so bad that you would swear that something had broken! Regarding your jet, there is all sorts of things that can affect your jetting, so I am not sure that I would be wise in commenting on that aspect of your engine set up, but let me ask you this: Have you looked at the top of your piston since you put the 165 jet in? That is the best way to know if the jet is the correct one for your engine on a particular day unless you have an EGT capability on your kart's gauges, such as running a MyChron 5 2T. I hope this helps, please let me know how things go for you and best of luck!

[@E.skrty.4]

Do you know what Jack's lap times were in the Honda vs the KZ? And were the karts running the same tires?

[@RKSiler]

Hello and thanks for watching-great question! While we did not get real deep into lap times, I can tell you that Jack was about 1.2 to 1.5 seconds per lap quicker with the KZ on tires that were fairly comparable to what was on my kart. The KZ is just faster everywhere, which we expected, even though Jack's speed in terms of mph was roughly the same same at the apex of each corner...the difference could be attributed more to Jack not fitting all that well in my kart vs his kart since I am about 6 inches taller than he is...Jack was having to "reach" for the pedals and he was sort of flopping around in the seat since I am also wider than he is, so that probably slowed him down. Still and all, the KZ, on a very tight track with short straightaways, was still significantly quicker. On a modern, long track, the difference would have been pretty stark.

[@alvintarrer6914]

Ya'll close to my age...awsome...I feel better now at 68,but no cart 👍✌️

[@RKSiler]

Alvin, you are not too old to give it a shot! I have a friend who is 70 who races shifter karts and he is very competitive.

[@alvintarrer6914]

@@RKSiler have to sell my harley

[@tatotejeira2845]

honda 2021 ?

[@mediascapes2011]

Never thought of the KZ engine being like a sewing machine, I thought it's closer to a chain saw.

[@p.c.h.6721]

How about comparing a TM with an IAME 175cc Shifter

[@beginagain8101]

That is a wonderful idea! I need to find somebody in the area with the IAME engine but that said, once I find that person, consider it done. Maybe the best idea is to compare the TM KZ with the IAME 175 and the Rok shifter engine. That could be very interesting! Thanks for watching!

[@p.c.h.6721]

@@beginagain8101 Looking forward to that video, my money is on the 175cc, although if the track has too many tight corners and short straightaways, them probably the TM would come on top, but not by a lot. Stay safe and enjoy ✅

[@p.c.h.6721]

@@loopie007 Thanks for the information, I have an IAME 175, I bought it very recently, but it has given me a lot of problems, mainly the is one particular corner in my local track where the engine bogs down every single time, only while in second gear, it took me a longtime to figure out that I needed to replace the pressure spring inside the Tillotson, it came with a 42gr spring from the factory and I just replaced it for a 48gr spring, it has improved a lot, I need to do more testing as I haven’t had the time to go to the track lately, I hope that problem has been solved for good, I also purchased the Dellorto carburante to test the engine with both carburetor and see which one comes on top, because of that problem with the spring in the Tillotson, I haven’t been able to test the 175 against all the TM R1 that are racing in my local track, there’re a lot of them, so I’m looking forward to it, and yes even if I’ve driven the 175 very little, I’ve noticed the torque, it’s incredible, I hope I can come on top when racing with all my friends that have an R1, any tips?

[@sw653j]

What's needed is entry level stock Honda only class...cost of KZ vs Honda...

[@RKSiler]

I agree...it would be really nice to have a stock Honda only class, which would be fantastic for beginning shifter kart pilots. The problem is that parts are now becoming hard to get for the Honda ( so I am told, anyway), so really the only choice to take is either the KZ or the Rok

[@jordanr3918]

@@RKSiler Yep, can't risk any bottom end blowups. All the parts you would need are out of stock or priced absurdly. If you have a bottom end seizure and you somehow damage one of the cases your SOL and stuck trying to repair it.

[@jracer7189]

Yahama makes shifter kart engines HZ shifter