Dr.Jekyll -> Mr.Hyde conversion formula ;)

[bikelover]

This is the story of another satisfied customer at RDDreams

Flash back time - I joined this site in 2002. Back then, I was working in Hyderabad and had a cbz. I found this site by chance when searching for how to get more performance out of my cbz. After going through the posts here, I slowly came to realize what kind of potential lies within a 2stroke motor. You see, I had been driving 4 strokes all the time, and was not used to the power delivery of a 2 stroke.

I moved into Bangalore towards the end of 2002. Having sold my cbz, I was itching to get a 2 stroke. I got myself a Yamaha RXZ 5spd last year (2003). The stock bike makes 14bhp@7500rpm and has a top speed of about 110kmph on the speedo. The bike made acceptable power in the lower rpms but had to be wrung to 5500rpm to make serious power. After the warranty period of the bike got over, I decided it was time the bike got a treatment from the man himself. Then started the visits to the doctors place

As I am not used to high powered screamers, I had wanted a more refined motor but with extra punch in the powerband and one with reliability too. Ron has been extremely patient in answering my questions/doubts/concerns and has been extremely helpful. So what we have here is a Pre-Stage I evolution in the form of

RX135 5 spd barrel bored out to take 60mm piston ( stock is 58mm ) and ported by RDDreams.
RZ reed block with glass fiber reeds
Keihin pwk carbs
RDDreams digital CDI with wasted spark removed and rev limiter set to 11000rpm

The bike is running on stock pipe. The motor has been run-in (completed about 1100kms mostly within city limits with occasional drives in the ring road) and manages to touch 120+ on the speedo. The acceleration is very crisp in all gears.

The bike turns from Dr.Jekyll in the lower rpms to Mr.Hyde in the midrange with just a twist of the wrist

There are some more goodies planned by Ron for the bike and am sure its only going to get better

Thank you so much Ron

Going back to the ring road to get a feel of the power band again
Vignesh.

[Myth_Pharoah]

Nice... and RXZ with the looks and the power... lucky *bleep*! :p

If I'm not mistaken, ring road is a road that circle bangalore and is cemented or something right? I hear a lot about it lol.

[chinoy]

Hey man glad you like it.
Got to be one of my hardest rebuilds ever done. Why cause
You cant bulshit an old RD Dreams member they know too much lol.

But the real reason for it being hard was because of the type of engine asked for. Which was low end should improve. More power thru put the power band WITHOUT shifting the power band. Instead the power should start earlier and rev out more. And achive all this without chambers.

Lets just say one of the most challenging rebuilds done to date. Power band starts a little before stock bike. And pulls to 9000 RPM in first 3 gears. The new piston took it from 132 to 140cc. The Banshee reeds are multi frequency tuned and the Kehin flat slides help in providing crisp throtel responce. The Digital CDI has a custom curve that boosts power in low and mid and retards thru the power band.
The design objective was to make it a fun bike to ride in trafic not a screamer or big BHP numbers.
Next stage is a Hiden chamber. And yeah we dumped the 11Kg cat can in favour of a lighter stock pipe. And next to next stage would be RXZ170cc.

[bikelover]

The figures from my experience with the stock motor.

Stock motor
--------------
Power band starts @5000rpms
Barely managed 8k in 4th

Speed achieved
in 4th gear (speedo) ~100kmph@7.5k
in 5th gear (speedo) ~110kmph@7.5k

Fuel efficiency ~29kmpl
(With blasts to redline in the 2nd & 3rd gears and max cruising approx @60 within city limits).

After living with the bike for a few days, heres my observations.

Rebuilt motor
---------------
Power band starts @around 4000-4500rpms
Redline achieved (in first 4 gears) 9000rpms
[Actually didnt have the heart to rev it out more]

Speed achieved
in 4th gear (speedo) ~110kmph@9k
in 5th gear (speedo) ~120kmph@8.5k

Fuel efficiency ~35kmpl
(With blasts to redline in the 2nd & 3rd gears and max cruising approx @60 within city limits).

The way the power builds up when in the 2,3&4th gears is AWESOME !
All I can say am in love with this motor and I want more

[chinoy]

Man I knew the mileage would improve but this is simplly amazing.
So all those nights spent tweaking the scavenging effiency and port angles in Vaniks software actually paid off. I guess the huge spark helps too. As do the new carbs.
Better keep a close eye on the bike. I know a few guys who would love to see how we pulled all this off.
Heck maybe I can sell the design to Yamaha.

More you say anytime Bro. I know just what to do. We will boost power and re-sprocket to get you into the 130-140 range.
A pic of the bike would be nice. Remind me next time.
Ahhh a shinky brand new RXZ140 that does 140.
I want one lol.

[bikelover]

Better keep a close eye on the bike. I know a few guys who would love to see how we pulled all this off.
Heck maybe I can sell the design to Yamaha.

Serious Ron, my friend who owns a similar bike ( 2002 RXZ 5spd ) was thoroughly impressed with the bike and was even more impressed with the increase in fuel efficiency

A pic of the bike would be nice. Remind me next time.
Ahhh a shinky brand new RXZ140 that does 140.
I want one lol.

need to clean the bike before the pic.

Thanks for the advice to run premix Ron.
I feel the bike is smoother compared to when it was running autolube + premix and the throttle response is crisper now

[bikelover]

Ok, time for an update now.
The bike has completed about 6000 odd kms till date after the initial rebuild. I was using a rubber boot connector for carb - air box and that has not been a tight fit. This + my fiddling with the inlet manifold creating an air leak ( broke the stud bolts ) has resulted in the rings wearing out. Got the rings replaced at the doctor's place - the motor is back to its original shape now
I have not checked the performance figures lately, the bike did 124kmph on the speed gun the last count. The mileage figures are hovering around the 30-35kmpl mark depending on the driving. I have taken the bike twice to Nandi hills with a pillion and another short distance tour, the bike rides stress free.
Will keep updating.. Thanks Ron

[chinoy]

I dont think any of that matters.
The rings still had good life in them. You could have run them for another 4000 Kms at the very least. But as the rings are only Rs250 a set. And we had the barrels off I thought why not.

After 6000 Kms the bike had no carbon build up anywhere in the exhaust or transfers.

For any two stroke to maintain compresion pressure and mileage the rings should be changed every 10,000 Kms.
I know you can run the same rings for even 25,000 kms but perofrmance and mileage will go down.

I think we can get the mileage upto 40 Ill explain when we meet. Just need to change your timing curve a little bit.

[bikelover]

I guess its time for another long term update. I've been running pretty much the same setup except that the barrel has been replaced with a RDD street port 5spd barrel running .25 oversize piston (around 2005 end).
The rest of the setup - RDD digi cdi, Keihin pwk, Chinoy Filter are the same as what it was 4 yrs back. The bike has run over 15,000 kms with this setup and has seen 5 track days at the Kari speedway now. And it is also used for commuting within city from time to time. Till now the only things I've changed are the fluids and consumables like brake pads. The bike starts up and runs crisp without skipping a beat all the time. Everbody who has ridden the bike has come back with a big grin on the face everytime.
It takes great pride for me to say I have a RDD built bike. Thank you Ron.

[chinoy]

Thanks for the kind words.
Very thoughtful of you to remeber after all these years.

The sucess of your build and story is no small part due to your attetion to detail and doing everything your self from spliting the cases at home to runing it in carefully.
Guess on a pipe that puppy with jeting will be the next Evolution. You saw the change a good pipe brings.
Plonk on the Rearsets and drop off the bike.

Days like this make it worth doing what I do. They are few and far between
THanks for everything.
Ron

[gunnniboy]

Dear Ron, shall I email you now?

Needless to say, I want the SAME treatment for my baby too!
And, I am sure that, I can convince my Appa to fund for this project when he hears that it will also improve the mileage! Heh heh.. What say Guruji? Game on?

My current setup:
5 Speed Block + Piston + Head
4 Speed Carb
Chinoy filter with size 175 jet that you sent with it
RDD Digital III CDI
RDD 90/100 Kit
16 x 39 Sprocket

What the ****! If it's gonna gimme ~35 to a litre, I might as well compromise with the mileage by 5KMPL & plonk in a custom pipe too

[vivekjayasheel]

We Indians want EVERYTHING

[crazydiablo]

Awesome man, just awesome.....

Vignesh, lets start work on the bike soon.

[bikelover]

@Ron - I agree, pipes is the next evolution. I'll get the right set of rear sets this time and will drop the bike at your place for the pipes.
@crazyd - Yes man, we'll start doing the work in steps so that we don't go through this exam syndrome

[bikelover]

Well, time for another update after all these years. The bike doesnt get to run as much as the Karizma has taken over the commuter duties almost full time. However, it has been used on many track days, ridden by many people. All of them had one thing in their face after coming back to the pits - a big grin all over the face. The bike was dropped last to last track day and Mohit helped with getting back in shape. After that, it was idle for approx 10 months or so. The battery had conked out by then as well. Last weekend we had a track day at Kari and Anand wanted a bike for the instructors to use. We cleaned up the bike and checked fluids, lubricated chain, topped up air put in a new battery and presto - the bike started in the first kick !

The bike was then ridden on the track by Joshua/Prashi/Anand and all of them were praising the way the motor revved and made power everywhere. This is a testament to the RDD digital cdi as well the RDD build. Thanks again Ron for this bullet proof setup, it is simply awesome

[SunMysore]

Can vouch for Vignesh's setup. Bulletproof indeed while not compromising on fun!

[chinoy]

Thanks for the update man.
LOL and we built this bike in 2004.
Its been to a shit load of track weekends and its still running.
Shit I amaze my self sometimes.

So much for people saying modded reliable two strokes are not possible.

The sad bit I will probably never ever have the time or patience to build a RXZ like that again.
Look after her. Its a rare piece of art.

[chethangowda86]

@bikelover hi sir can u plz post some pics of your bike if u don mind.. i have a rxz 5 speed with cdi and Chinoy Filter. looking to upgrade a bit.. plz advice..

[chinoy]

LOL every RXZ owner is going to be wondering why cant I get my bike to be something like that.

Well Ill tell you why. you dont have half the passion bike lover had.
Let me tell you the story of a young man. Who loved bikes.
He got his first job in a far away city called Hyderabad. He loved bikes so he purchased a CBZ.

He then found RDD and asked how do I make my CBZ go faster.
My reply was sell that piece of junk four stroke, buy a RXZ and get it some RDD treatment.

So he found a job in Bangalore, moved to Bangalore, sold his CBZ and purchased a brand new RXZ. On the day his warranty was over he brought the bike over to me.
And said do the magic.

Now I have had guys come to me. And try to throw attitude or even look at me the wrong way and say stuff like do it or I will take it to XYZ Racing and get them to do it. And nothing gives me more pleasure in telling these guys please help yourself take it there and get it done.

But no bike lover had a single minded determination. He had passion and he had faith.
Not once did he doubt. Not once did he question not once did he say do it or I will take it to XYZ. He just handed over the keys and the money.
The out come was pure magic. Even I cant believe how sweet that motor is or how its still going strong. There is some magic in it.

[chethangowda86]

@ chinoy - sir i agree that i dont have half the passion bikelover has, but even i waited for 8 long years to buy my ride.. travelling by bus all the while (declined my dads offer to buy me a pulsar 220). llike every newbie i was skeptical about rdd at first, only after the cdi install did i realise wat lay in store ahead i m no racer guy... just wanted to experience the magic of a 2 stroke and enjoyin i am..after the cdi and Chinoy Filter..

sir i m savin money hoping that one day u ll accept to rebuild my bike... when i have the money i ll call u up. plz consider my request sir... long live rdd