Everything is because you have posted the results of/your opinions about the modifications on your bike in a public thread where all of us participate in the ongoing discussion.
I am not at all worried about the effects of the modifications on your bike but expressed my opinions as you yourself did. Please don’t be felt insulted.

Absolutely right... Nowadays I used do shift gears at higher rpms frequently... Following full clutch method..

Within a week of purchase I changed the indicator to no blink mode.. No plan in getting back to it .so I've to change my mind set..

Riding at speeds of 70-85kmph with more stop and go conditions..sometimes touching 90..
And even at these conditions too it delivers a good average of 52kmpl approximately (For 2.87litres of fuel - 150kms covered)..

Without any mods it's already doing its good performance..

Yes. You dont need any mods to reach those speeds. So, it must be the first time manu has redlined his bike in those gears.

But, this "improved acceleration" can be quantified by launching two gs's side by side to see who is faster.


Its always good to have skeptics around to keep us grounded.

Manubhat can give you your answers with proof on both counts. But here is my attempt anyway. Correct me if im wrong.

Possible reasons that companies dont do this:
> Like ashwinprakas said, to increase an engine's reliability or operating lifespan.
> Target audience or price bracket. The bike is targeted at a certain segment for which such additional development expenditure\efforts is not necessary.
> If in case a demand should arise for a bit more power, companies could respond to this by doing such modification work to the existing design....assuming that they might have already engineered some room to accommodate such modifications into the original design. If joel's modification works, then they have.

Such room for improvements could also be inherent with any engine design. Or it could be the modifier's insight into engines that lets him see such possibilities for improvements that others fail to.

Of course, this is all theories and assumptions. But none based on thin air.

Now onto the FE part....while manubhat can probably supply the facts to dispel your doubts, its not hard to believe that an increase in powr can increase FE as well. Now I dont know how porting can increase FE. But I remember reading somewhere that an increase in compression increases torque by a considerable extent, so that it takes lesser throttle to move a gear at the same speed as it does to move it at lower compression. So, increased FE. But at a cost.

Lets suppose that there is an increase in FE due to the mods. This FE gain is offset by more strain on engine components due to the mods.

If there is an increase in torque(which is the point of this mod business), there must be more strain on the piston, crankshaft and all related parts that are now needed to function at a higher pace than usual. So, more wear and tear overall.

Here, 10% increase in FE means 4.7 kmpl extra over company claimed 47 kmpl(city riding conditions). Thats a savings of about rupees 1500 (at the current petrol rate of ~ rs.73.5 in bangalore) for every 10000 km of operation. More power means chances for increased clutch wear, chain\sprocket wear, tire wear, decreased operating life of spark plug and air filter and god knows what else. So, that FE savings is meagre compared to the potential for escalation of running costs due to faster wear of components.

+ most of the target audience is more than happy with what the vehicle is capable of and probably dont even approach the vehicle's limits.

So, even if it is possible to increase FE by such mods, its no wonder why suzuki dont do it themselves. No wonder gs150Rs and unicorns are seen as less troublesome than apache's and pulsars that make more power than our bikes do, at the same cost.

It appears that power output, FE/running costs and longevity of the engine are linked by a balance. Any 2 gains happen at the expense of the third. Or any gain happens at an expense. It is upto you to decide which gain you value more.

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@manubhat: test out against a stock GS, preferably one that has run lesser than yours.....and let us know man. Acceleration and mileage wise.We are curious.

Chill mate..you are free to express ur opinions..I was just trying to say that there is some improvement in acceleration.. so lets take the discussion further and try to find out if there is any real improvement in FE and power


Great!!That is some serious mileage for the riding style you mentioned...I never got above 45kmpl with almost same riding style and petrol was from Trustworthy petrol bunk(SHELL).....
what i used to get is 105kms for 2.63litres...it comes upto 40kmpl.


well said 2strokerama
Iam not fully sure about the performance and FE yet...Am just trying to learn everyday through forums and discussions...
Also Am more curious than you to know how my GS performs with stock Bike....I was thinking about the same from yesterday..As am riding her more and more,i feel that there is only a slight improvement over stock...
Am not able to differentiate between how fast the bike was before and how fast it is now? so i need all your valuable suggestions guys...

MSN are you listening..Ping me if ur free today..lets do a test run

I am from bangalore and i will be happy to test out the bike. I have also contacted joel recently and he also said that he would maybe look at my bike..so...i would like to see first hand the difference if any...PM if you are keen to ride...

@ALL - Has someone confirmed the actual reserve capacity of our bike. I have a feeling it is not 3.5 approx as advertised but less than 3...has anyone checked this??

Great!!That is some serious mileage for the riding style you mentioned...I never got above 45kmpl with almost same riding style and petrol was from Trustworthy petrol bunk(SHELL).....
what i used to get is 105kms for 2.63litres...it comes upto 40kmpl.

My GS is very pocket friendly compared to my HH P+.. I used to get around 45-50kmpl when riding at 70kmph's in passion plus with less comfort and safety... I used to fill UNLEADED Petrol from random bunks (mainly HP & Indian Oil & sometimes BP)...

i live in the same area where manubhat lives and using the same petrol bunk
my driving style is like 5 or 6 kms per day and used to fill 2 ltrs almost every 8 or 10 days once.

speed is not more than 45 or 50 as the ridding place is small and narrow roads

moreover almost 50% of the times the pillion + rider weight to-gather is 150+
the mileage am getting is in between 44 to 48 kmpl.

the last one bar on the digital meter refers to approx 3.5 ltrs
after the bike hits reserve i believe it would be around 2.5 Ltrs

Hi guys,
Finally I've got my new GS150R Black 2012 model. Will be uploading pics soon. The odo read 3.8KM (ODO only showed 3 KM but trip meter was more precise).
Took it to Gurudwara (as instructed by parents and friends). Not driven long, since I got it ready late evening. But enjoyed riding it a lot(sort of craze of riding). Though there is one minor prob, one pilot light not working so dealer said he'll replace the whole front thing with new one(I couldn't wait for another piece as I'll have to join office from Monday). Also, gear shifting seems quite different from the previous GS150R, in my old bike I couldn't get Neutral(except when engine was off) and in new GS150R, when changing from 1st to 2nd gear, neutral was messing up.

hehe, but last week i rode for some 100kms after hitting reserve and the bar still didn't begin to blink

Have you ever reached 12,000rpms on your own bike ????

I guess not, that is why you are jotting down theoretical figures here.

In doing so, you have discounted the weight ,aerodynamic drag, engine power ,compression ratio and gearing ratio of the bike it seems.

I admit that there are a lot of tools over the net which will show those theoretically possible figures after factoring in gearing ratios and tyre size, but none of them are meant for the specifications imparted by the GS150R in stock conditions.

I say this, not to you personally, but in answer to your doubt that, my GS150R does reach 12,000rpms in sixth gear clocking 127kmph on a normal plain highway(no downhill) in presence of cross winds.
I admit it is not a stock bike and that difference can be felt,my stock GS150R in a similar situation could have at the best done 119kmph and would have taken eons to reach that 127-130kmph zone.But the mods on my bike has shown the effects.

I have clocked 95kmph in 3rd, 105kmph in 4th, 115kmph in fifth and 127 kmph in sixth on my boosted bike.......all in redlining zone of 11,500rpms.
I can blatantly say that it is not possible on a regular GS150R.

I have done nothing to decrease the weight of my bike , not even changed stock tyres and brakes.......but I feel my bike surely has got an upper hand.

Now, coming to the question when the power and mileage both are mutually benefited..................., you have to say that why paid engineers at big corporations do not apply such tech right--
But I can tell you, half a century back, many cars with big engines made as much performance as our 150cc bike does now, with a lot lower mileage........reliable technology always evolves the vehicles,but raw race tech is for the track not for the general public, hence engineers have to think about the revenue from everyone while building a machine.But ultimately raw tech makes it to public in a refined acceptable way.

Everyday folks won't go and buy a Busa or ZZR1400 with a lot of low(but reasonable)mileage and rocket ship like power, but still they are produced for folks who earns and yearns them and they are sold too.

I am impressed and inspired by Joel's work on Manubhat's bike- however little difference it makes and my friend(who gifted me his self-made supercharger/developed it for my bike) has already started working on his own ways of increasing my bike's Volumetric efficiency, so that the boost can be used more efficiently, and we would start with porting- just what Joel has done on Manu's bike.

Finally I've got my new GS150R Black 2012 model.