@ JD..... Are you talking about xx BHP @ yyyy RPM, for example

RX 135 4-Speed : 12 BHP @ 6500 RPM

Shogun : 14 BHP @ 8500 RPM

P 150 : 13.5 BHP @ 8500 RPM

Unicorn : 13.3 BHP @ 8000 RPM


Shogun has the best BHP / Ton ratio, has a very good RPM range, has a good gear ratio setup & still does only 105 Kmph. Why?

Just a thought here, i have a very good fan of F1 racing & out there the most important thing they talk about is Aerodynamics. So will the top speed of a RX 135 5-Speed increase, if we fit in its engine in an R-15 chasis & buildup? This is just a wild imagination of mine.

actually I think,the more power at the free revving end, the better the top speed registered.
Which means High end torque and power.Suzuki Shogun revs at 10,000 rpm at top gear, very similar to Fiero(the original).Since I have both bikes,I can tell their nature.the Final drive of both bikes is different.Suzuki Shogun has attained a 112kmph(speedo indicated 120kmph) under me beyond which I dint push the bike as it had not at that time good stability (it was just at 8300rpm then),Suzuki Fiero did a speedo indicated 129 kmph,I dont know what was that in reality,the classic Fiero doesnt have a rev meter and so I failed to judge the rpm at that speed.

What I felt Fiero is attaining this Top speed easily, only bcoz of the 13/39 final drive it uses.Suzuki Shogun on the other hand is heavily honned in for acceleration at 13/44.Company manual shows it has 105kmph as top speed.Whereas I have seen it exceed in stock gearing !!!!!!! May be the company has this speed as the recommended safe Top Speed.Because beyond that the light bike catches every single crosswind,I gotta work on that,since I would be increasing its top speed......seriously tyres need to be a lot better than its normal set.Consider using the thin sets on the Yam R15.I think the Shogun will fly.Also,I got this implication that it also needs heavier front shocks,like Fiero's.

I was also considering a five speed gear box for a better Top end,but I was corrected here at xbhp,maybe by Joel or someone.............sorry I cant remember
Shogun doesnt needs the fifth cog, just see the fourth gear ratio.Its the same for bikes with the fifth cog !!!!Shogun's got a taller second gear,which means the third gear can work a lot......I seriously wonder what are these bike's potential or why was this bike developed this way ????? TVS still uses the Shogun at their races and they are usually the champs.

a gearbox cannot simply be made keeping the top speed in mind. It has to match the power and torque curve of the bike, and be optimum in every sense. Factors governing gearing for a street use bike are -

- Amount of low end torque available ( which translates into lesser gear shifts if the torque is high ).
- power being produced at commuter speeds ( 40-60kmph ), whether the bike can manage it in top gear, or will the person have to downshift. If the speed will be maintained in a lower gear, it translates to higher engine rpm, which increases fuel consumption, so thats a no-no
- Driveability of the engine and bike with the max rated load. You can give it tall gearing, but will the bike accelerate and run smoothly at full load??? So the gearing has to be altered again.
- The final drive can be toyed around with, but the internal gear ratios are tested and decided keeping all these factors in mind.

hence a race tuned bike will have a different setup of gearing even than the street bike.

@mach50 - since youve had both bikes im sure you wouldve noticed the difference in performance and acceleration when you were riding with a pillion on the two stroke, and then on the 4 stroke.

what u gonna prove

Shogun was faster off stand still with a normally weighed Pillion on board, and also sometimes wheelied!!!!!!!!! Fiero just went about without complaining with the same person as pillion, I mean its fast too but not fast as the Shogun.
However Shogun felt more planted at 90kmph with pillion rather than single.I dint go beyond that with the pillion,with my mind at safety.Fiero is always more stable than Shogun at high speeds and with pillion, it was same.

TVS racing uses a close ratio gear box,with 6 cogs for its racing Shoguns,its totally different from the street gearbox.It has both acceleration and top speed.My friend had used a close ratio five on my bike itself.But since he gave it back to me,he installed 4 geared original.He told me, that his gear box used to stress the bike a lot.He developed it for himself and was not a Suzuki specified one.

Karthik do those gear ratio numbers account for final drive ratio, primary reduction ratio and wheel diameter? If not you have to multiply each one with the corresponding gear ratio in order to get a ratio of crankshaft's angular velocity to vehicle's linear velocity. If an RX truly makes more power than a fiero and both the bikes are geared identically such that once in top gear every crankshaft revolution results in bike moving exactly the same distance, it will go faster than a Fiero. The only way this couldnt be possible is if any of the other factors like total vehicle weight and aerodynamic drag are not equal.
In addition, another reason which could be a possible explanation is that the 2 stroke power numbers quoted in the magazines could be a lot more optimistic than those mentioned for the 4 strokes. Most of them(2 stroke power numbers) were published in an age when dynos were a distant dream for the common man. Such a comparison would make sense if its between 2 vehicles which have been tested on the dyno.

2 stroke power were rated by companies and were dyno tested.Companies like Yamaha and Suzuki had been in into 500cc 2t GPs for decades, they are pro at power setting and dyno rating.Both Shogun's AX10 engine and RX100's 85-89 engines were direct imports from Japan.So no doubt that they were dyno-rated figures.It is known by all that 2ts actually goes like stink and it does.Basically all these legends were released in India for commuter public and so they had toned down outputs.But in this age of mods, they(100cc-140cc 2ts) can smoke anything till 230cc 4ts(and modded ones too),with the correct mods.Yes their fuel bills would be high.

@jd666........Yes I have read the Autocar RX100 vs FZ16, and it seems that RX100 couldnt have had a better successor than FZ16.You can tell that FZ16 is actually the new RX100.The magazine tells though, that RX100 needs to be ridden by right hands to keep up with the FZ16.And its also correct,only Pros can ride the RX100 the way its meant to be ridden,while anyone can hop on a FZ16 and speed off.Pros can handle vibrations under hard acceleration and clutchless shifts,which are the traits of a fast RX100.While on a FZ16, its very easy to ride, as these niggles wont be there.

RX100-11BHP/10.74Nm torque,[email protected] secs precisely
FZ16 - 14BHP/14Nm torque,[email protected] secs precisely

Even after this they call RX100 the Usain Bolt of straight line where the enormous power to weight shows and measures the FZ16 if not passes it in gearshifts.So, it can be well understood that even with 3bhp less and lower torque,how the 2t engine keeps climbing the RPMs without any power lags.The newer,advanced,aerodynamically favoured,midshipped 4T FZ16 seems to be needing a breather in order to keep the game up with RX100,which is a 15 year old bike with basic technology.
Supremacy of 2T engines can be well understood here.

@MACH50 : I do not mean any offense to you but I disagree with you about some things. The traits of any powerful machine are only performance figures. By that I mean dyno results or 0-60 results. A fast machine does NOT need to vibrate. Vibrations are a a trait of a poorly designed vehicle or component within the vehicle.

Not meaning to get into any arguments here... Is this figure mentioned in the article? I was always curious to know RX100s acceleration figures.

^^ yup i think so it was mentioned in the article.

Hmmm.. thats in the Gladiator region I think... Pretty pedestrian considering the reputation

Macho50 . u must be a mathematician to judge a bike by number crunching . Theory and practice and two entirely different things my friend . FZ a nice bike with a slow mo motor .

where is the disagreeable point in this ???? U r correct.And I never wrote anything that disagrees with your point !!!! Moreover these 0-60 tests are never performed in absence of crosswinds and so they are seldom error free.Lighter bikes with conventional chassis suffers.The real magic of better power to weight can be understood when these smaller engined 2ts keeps accelerating even after 90kmph to their top speed unabashedly.Whereas more relatively bigger 4ts,it requires sometime, rpm slotting and all to keep the machine accelerating to its top end after 90kmph.

@Vampire........I am not judging the FZ16(torque maestro) and RX100(Ok, torque monster) on my own,its just a recap of the Autocar article, none of them my thoughts. Thanks.U must have confused me with Rkoli1983 who is more into number games rather than street logging

Yes i fully agree with this one.

What was the summary like !!. What were the Top-Speeds mentioned & how were they measured?

This is so true even in case of smaller 2-Stroke machines like Hero-Puch, which accelerates till 60-65Kmph (Top Speed) effortlessly. The way indian 2-Strokes pull till their respective Top-Speeds is commendable. No wonder they call RX as "Pocket Rocket".

And all of us, please let us maintain some peace here, we are just trying to figure out if BHP/Ton ratio is infact important in Vehicle's performance. No offence on RX series here. They were the greatest bikes ever produced & will continue to be Legends.

"And all of us, please let us maintain some peace here, we are just trying to figure out if BHP/Ton ratio is infact important in Vehicle's performance. No offence on RX series here. They were the greatest bikes ever produced & will continue to be Legends."

To answer that, bhp/ton ratio cannot be the absolute measure of a vehicles performance, since the power and torque curves, the spread of power, how it is utilized, and the gearing employed to widen this power further, all make a difference to the vehicles performance.