Yes accepted. But you are an expert track racer bro. Being honest, if required for me to brake hard from 136Kph, I will have lot lesser confidence than you . But still larger disc plates do make a considerable difference.


To answer very noob, my stock bike will do 125Kph upright and 135Kph when tucked in. Will take a long time to reach 140+. With this setup I can do about 138Kph upright and 157Kph when tucked in. The speedo lost momentum after 150Kph and took a few secs to dial the next digits. At last as usual ran out of road. An FFE and a hotter cam profile will show some real time performance. Its way faster from 0-120 just like it used to do 100 before. Faster than a stock Duke, coz R15 sprockets yield a good topend compared to its competitors, now the gamble is on HOW FAST IT DOES IT?

There are two things that are restricting the current performance,

1) Stock Cam
2) Stock Exhaust (Cat removed)

Tried different cams, branded and non-branded. I did not find the balance as like the stock cam. Either it was good at low-mid or high end. Also it was hard to make a provision for decomp assy (to avoid more cranks to start). The reason to avoid FFE is that I strictly want my bike to be as silent as possible and retain the quiet nature of a stock R15. I avoided the Air-box modd too, due to intake noise and moved on to Ferrox Airfilter.

But end of the day, I use my bike daily and munch 1000s of kms every month. So I have to give up at times to retain the reliability and respect. No offense to any FFE users.

Yes exactly what I am up to say. Its not as easy as we speak here or advertised here to move onto a bore-up kit. I have seen many users investing about half a lakh on the bore-up modds and end-up with nothing. I personally resold those left out parts for peanuts.

If anyone is capable/knowledgable on bore-up modds and ready to convert it into business, then he should personally take care of the entire job from A to Z personally with his hands/supervision and finally provide a warranty for a period of time. This avoids a lot of mess and finger pointing. Most welcomed by all customers too.


Also Bro, one thing I have to mention here, there is a lot of quality difference between the after market bore-up kits sold in the south-east. Mainly between the Branded and Non-Branded ones. If we get a chance to meet at the Chennai track sometime, just take my bike for a spin, you will notice the piston operation at any RPM to be extremely smooth, slient and in rhythm like a Honda . But I never got such a result with the cheaper non-branded ones.

Hi bro,
went through your thread, I must say you've come a long way and many congrats for the feat that you've accomplished.

I too am a person looking for more performance.. A couple a questions I have, would be glad if you could answer them.

1. Is the UMA 60mm kit a direct bolt-on on the R15's engine? These are basically kits for LC135 so is there any modifications required to the crankcase or any other part??

2. How can I get this kit?? Also the various parts like the filter and denso 10 hole injectors..

3. There are images of a 62mm kit with a power output claim of 28bhp? what about that kit??

Thanks,

1) UMA has only 62MM Block/Piston kit for LC135/FZ150i/R15/R125. Direct fit. No modds required, even the gaskets are provided in the kit. So issues any where.

2) You are already in touch with me at the link below in the signature.

3) Not sure, thats the claim with the UMA Brand 62MM kit, 32MM TB, High lift cam, UMA Super head and FFE. All these are claimed on LC135 which has a stock power output of 13HP, so should be more on R15.

Need some help on ECU mod on my r15

Hi Everyone,

I am trying to learn something from the ECU in R15. And I have some question regarding the mod on the ECU.
Currently I have 2 bikes to experiment with the following setup:
1. R15 Version 2 Black
a. Ported head.
b. Increased the compression

2. R15 Version 1 Black
a. Big Valve head
b. Race concepts cam without the decomp valve.
c. 61 MM bore kit.
d. 13 teeth GB sprocket
e. 42 or even 44 teeth Rear sprocket
f. Race concepts Air filter.
I am trying to learn about the ECU Mod for both the above bikes
I just want to know some details and answers about r15?
1. What is the AFR of stock r15?
2. What should AFR for the above setup?
3. What is the optimum fule1/ignition/correction setting in the race dynamics rtune software?
4. I know that if the fuel is very lean then it a problem but what if I over fuel it?
5. Will FI diagnostic tool help me to correct know the errors that I make?

Please suggest maybe I can try on my bike

I will keep you posted about the pics of the Race Dynamics ECU tuning software.

I am not sure what everyone has to say, but my views.... none of the so called tuners in India will have an accurate map for your requirement coz they simply don't have the machinery required to diagnose and setup the accurate map. All ECU remaps are done in trial and error method. If you don't believe in my words, simply purchase an ECU and go behind them for an accurate map you will understand this Fact.

Not sure about Race Dynamics though.


Upto my knowledge it impossible to read the stock ECU map and so is the stock AFR, for a modded setup rich fueling will not have any immediate effects while lean is a big no no... Lean fueling has the potential to screw up even stock setup.

About broken rings and broken dreams!

I would like to provide a update about my Race Concepts modded R15. My bike had 165cc big bore + RD ECU + stiffened valve springs + air filter + clutch springs. Everything was done at Joel's workshop.

It has been over 7k kms now. This included 2k kms on the highway and rest in the city. Initially, the bike performed well enough and I was mostly satisfied. Yes, the setup was not as polished as the stock setup and everything was a little rough around the edge. Small issues like non linear throttle response at some rpms, engine shutdown at idle and vibes at around 4k and 9k+ rpms were my major grouses. Also, fuel efficiency was same or slightly better than stock (with RD ECU). However, on the whole, I got what I was promised - a bump in power across the rev range. But I always felt that there was a tradeoff somewhere - what I lost was the refined effortless power delivery and what I got was a boost in the mid range.

Lately, the vibes had increased too much to the point that a 80kmph ride on the highway for 30mins would leave my hands (with gloves worn!) numb. Also, the power decreased at the top end - top speed was a mere 120kmph. Mileage down to 30kmpl while riding at 6k rpm and below. On the whole the bike started behaving worse than stock. Al this on a bike run for only 7k - that too with average rpm being kept at 6k with occasional burst to 10k.

At last I decided that modding in India was not my cup of tea and I need to revert back to stock. So, one fine day, me and my friend decided to strip down everything and replace the bore with stock 150cc unit. Much to our surprise, when we opened the 165cc bore, the top most piston ring simply fell in our hand - in 2 piece. On further inspection, the bore had some mild scratches too.

So, if I were to take liberty and judge Joel's quality of work based on my experience and those of others who have posted here, I would say its substandard. The product simply does not live up to the hype. And I did not bother to take this up with Joel and demand a replacement - I simply don't trust his works at all. To me, its seems his mods are designed to make the bike a one trick pony.

That's all - just wanted to share my experience here.

sorry to see your bad experience with the big bore upgrade, but surprised that you had gone for it. I think the sleeve overboring had not been good and the ring had seized and broken ...I presume this since the whole modification had been done at Mr.Joel's place, and so the work must have been done to spec,with adequate knowledge of the upgrade....
Hope your reverting to stock had brought back the R15 to it's original condition and a smile on your face.

I was about to update this thread today,

Very sorry to hear that from you, I still remember we both met Joel on the same day, I got all those modds and you just got an Airfilter. But being very honest, whenever my bike got stalled in the middle, I used to think that you were a lucky or wise guy to get an airfilter alone.

Not to blame anyone, but thats the quality of the block. These blocks are to be used on tracks and thrown away right there. Bringing them on street will unleash XXYYBHP gain and a 8.45642 Sec to 100Kph. On a longer run you will be fooled to run your ride with more compromises than what you gain. I openly challenge any big bore user for over 10K Kms to ride a stock R15 and compare it with his ride, the stock not only performs on par or outperforms his 165CC, rather the smooth engine operation will throw him in shame. The maintenance cost for the 165CC vs 150CC will tell you the rest of the story. I purposefully did not use a different cam coz the timing difference will be more tedious for a ECU tune and will screw up somewhere in the end as like Nv.Rohanraj lost his crank thrice. My setup is perfect with all elements in place. Branded UMA 62MM Forged/Nicasil Kit, UMA 32MM TB and Denso 10 Hole Fi, a much accurate stock exhaust without cat and a few more tit bits. I have selected the most reliable and best performing parts for my bike, but still as Nv.Rohanraj points out above I simply lost out in the basics, which is tuning my ECU to an accurate map. Got my RS version ECU from Joel and got a couple of tunings from him, unfortunately both returned ignition failure at FI diagnostics and drank fuel at random intervals. Got some guidance from many ECU tuners here and there none of them gave me an accurate map. I had a few spark plug failures due to maps done by a few local heads here.

This ECU tuning started to eat my brain, Again went to the same dilemma of giving up and replacing the entire bike. But yes I have done it all by myself and a thought struck in me to complete the ECU tuning myself. So finally borrowed an 02 sensor from my friend in Malaysia for tuning my ECU and got a user manual from Racedynamics and finally designed a map myself with the AFR ranging between 13.1 and 13.9. I have two strong conditions on the MAP, it should be running more mileage 40+ if the throttle is held low and should outperform anybike out there when the throttle is wide open. Hence the ignition and fuel values have been decided and it seems to be working

But still I am in the testing process, the bike ran about 44Kmpl under 6K RPM and occasional bursts upto 11K RPM. Regarding performance, TN07BR0212 who's ever Duke it was..... The owner may be in XBHP, Had a chance to compare my bike's potential with his Duke 200. From about 3Kms from Saidapet to Velachery signal he was literally pissed off, luckily the road was almost empty at around 2pm, coz at a few spots I gave him way to pull ahead and over took him in circles. Finally at Velachery signal he questioned me if the bike was modified and accepted that there wasn't anything left in the Duke to try more and also he was crouching appropriately. A few R15v2 and R15 owners/friends, the service guys took my bike for a spin at Sri Motors Yamaha and credited the stock like smoothness, excessive grunt at mid/high RPMs and also the front brake to be very sharp.

Already the FI tool did not display any error on the ignition front, so I am half way through. Next the mileage under 6K is 44Kmpl so 70% through. Next the performance, it simply gets up to 90% and the remaining 10% lies with the spark plug to tell me if I am right or wrong. All my hopes this weekend is to see my spark plug turning brown, with which I can proudly shout "I have tuned my ECU accurately". If it turns out to be a successful map and I don't want anyone to lose out his/her business here so just for awareness and knowledge sharing, if XBHP permits then I will be happy to share a screenshot of the fuel and ignition values and explain all the elements and with the information on why those values are present in each cell and how I am able to acheive the best of both worlds, mileage and power.

That would certainly be very interesting, Harishk, even for those like me who presently ride a carb. bike.
Please do not forget to detail all the information received by the ECU from the various sensors.

yes, YOU ARE PERMITTED, plz share your knowledge.

I had come across in various forums on how the Spark plug is to be read and would like to share it here...ever since lead had been removed from Petrol, the old school reading is changed ...Here is an image on the same..

your image is not visible.

Check your system settings, esp., firewall of both windows and Anti Virus, and display handlers..

Yes everything was done at his place.

Changed the bore and apart from that also changed the engine oil, air filter and spark plugs. The bike is back to its usual silky smooth rev happy self. I think I reverted back just in time before any major damages could occur.

However, the idle speed is still a bit low - maybe the throttle body needs to be cleaned or the stock ECU is still relearning all the parameters.

I threw out the air filter too! The Simota air filter was clogged with dirt. I could have cleaned it but I thought its better to replace it every 10k kms.

Be careful with the RD ECU. If the engine is cold and tends to shut down, on the last revolution the ECU fires the spark plug at random intervals. If its on the compression stroke, you will get a big bang. Happened with my bike.

Good to know that now the bike is smooth and to your liking....the back firing when cold could be due to advanced static ignition timing .