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**Bibhu** · 02-13-2011, 02:08 PM

If you got money (about 11 k) then go straight for the 220 engine mod, keep the gearbox and clutch of the 150 and go for the 220 cylinder and crank.

Less expensive: go for the 200 bore piston and head.

Go for the bs 32 carb.

if you want to put in the 220 cam shaft make sure that you got a working self starter otherwise it is very hard to kick start the bike.

I have done the 220 mod to my classic 180.

**princesirohi** · 02-14-2011, 02:27 PM

ok i will put 180 block pistion, replace valves and replace main jet with 180's main jet, if i put 220 cam shaft then....

is it not possible to retain kick with 220 cam shaft ..??
head and valves will be standard 150...will keep it as it is......is it ok...???

**pavanchirmade** · 02-14-2011, 09:08 PM

No the kick starter won't work with the 220F camshaft as the exhaust valve decomp mechanism is not present on the 220 camshaft. This mechanism is needed to kick start the bike. IMO the kickstarter will work but it will give you back-kicks. Everytime.

Don't switch to 180's 117.5 jet. After the camshaft mod you will need a slightly larger jet to make it work better. I don't know the exact number of the jet as I drilled it at home all by myself.

**princesirohi** · 02-14-2011, 10:18 PM

ok, so i will put a 180's block piston.

1) i will not change the crank shaft as i want to retain the kick start option. question is --- is it ok if i retain original crank shaft. will it be able to handle increased power and compression pressure. do we have different cams in 150 and 180.

2) head will also be retained as it is. what about valves. do i keep it as original. won't there be need of bigger valves to suck in more air fuel mixture and throw out burnt gasses quickly. do 150 and 180 have different valve head dia/length.

3) what jet size to use -- do i use 180's jet, if no, why?

4) is there a need to upjet, and if i do upjet, won't i require an equally increased air intake.

**psr** · 02-15-2011, 12:03 AM

Originally posted by princesirohi View Post

ok, so i will put a 180's block piston.

1) i will not change the crank shaft as i want to retain the kick start option. .
Mr.Pavanchirmade had clearly mentioned that the lack of de-compression, is connected with the P220 long duration cam..not crank.He is the first to do the mod and knows better.

2) head will also be retained as it is. what about valves. do i keep it as original. won't there be need of bigger valves to suck in more air fuel mixture and throw out burnt gasses quickly. do 150 and 180 have different valve head dia/length.
The difference between the 150 to 180 piston is 6.5mm,so corresponding change in the head is also called for due to the large nature of change in dia,and squish area.

3) what jet size to use -- do i use 180's jet, if no, why?
BS29 with 180's jet..

4) is there a need to upjet, and if i do upjet, won't i require an equally increased air intake.
This will come as the last mod and fitting P180 filter will do...Mr.Pavan is a better person to advice on this.

Answers in bold.

**princesirohi** · 02-15-2011, 02:41 AM

this is very confusing....

1) i have to change the cam and not crank shaft. ok. but that will increase the stroke and where will this increased stroke go....?? it will be hitting something inside cylinder and may be cylinder head or walls...??? ok. i m editing this post now.....i was thinking that i need to change the crankshaft. now i think i got it......u guys mean to say i need to change the cam shaft situated in cylinder head...that operates the valves...is it..??? how dumb i was.........i thought crank shaft......

2) is there a need to change the cam....can't we simply change the block piston.....and bingo...iincreased power.

3) Is it neccessary to modify the head....or stock one will do....??

4)is upjetting required and to wht size....i m not going to change my carb?

its 2.30 AM and i m going to sleep now.....hope u guys answer my doubts by the time i log in ......again in the day...

**pavanchirmade** · 02-15-2011, 09:27 AM

Originally posted by princesirohi View Post

this is very confusing....

1) i have to change the cam and not crank shaft. ok. but that will increase the stroke and where will this increased stroke go....?? it will be hitting something inside cylinder and may be cylinder head or walls...??? ok. i m editing this post now.....i was thinking that i need to change the crankshaft. now i think i got it......u guys mean to say i need to change the cam shaft situated in cylinder head...that operates the valves...is it..??? how dumb i was.........i thought crank shaft......

No you don't have to change the crank shaft. Crank shaft and the camshaft are 2 different things at two different places. The stroke length of the 150, 180 and the 200 is the same which is 56.40mm. Ok so you got confused ha?

2) is there a need to change the cam....can't we simply change the block piston.....and bingo...iincreased power.
The camshaft swap is not compulsory. But to enjoy better power you can install it. The camshaft is no big deal. Just 480 bucks and its totally plug and play.

3) Is it neccessary to modify the head....or stock one will do....??

Head has to be modified. If you look at the inner side of the head, you will find that it has a bowl like pit where you can see the heads of the 2 sparkplugs and the 2 valves. This pit diameter has to match the bore diameter. If not, the engine will either suffer pre-ignition or even damage due to very high compression.

4)is upjetting required and to wht size....i m not going to change my carb?

I have noticed that the engine runs slightly lean at higher RPMs after the camshaft mod with stock jets on my 180. So when I got the free flow air filter installed I corrected the jet size.

its 2.30 AM and i m going to sleep now.....hope u guys answer my doubts by the time i log in ......again in the day...

Answers in bold.
@PSR: Corrections welcome.

**princesirohi** · 02-15-2011, 02:14 PM

@pavanchirmade:

1) ok so i will install a new 220's cam shaft, do i need to change the valves also to that of 220, or valves are same on all pulsars 150 to 220.

2) how to match the cylinder head pit size to that of 180's block bore size. shops that do reboring job can do this or some special tool is required.

3) can u suggest jet size required - with or without K&N.

now things are clearing up bit by bit.....

other experts arer also welcome for suggestions.....

one thing i wanna say is that....my bike is my lifeline...i often go on long rides.......will this mod in any way reduce the reliability of bike/engine?

**pavanchirmade** · 02-15-2011, 02:43 PM

i have kept everything in the head stock.
I am using a 1.1mm jet. Don't know what number it will be. I drilled it myself at home.
Pit size has to be matched. The machineshop guy will know how to go about it.

**drvmtm** · 02-15-2011, 05:03 PM

why u r getting confused prince?

180 bore+piston is a direct fit without any change on head.
i told you to change valves because simple wire and tear till date with oem 150 s only,no upgread,just replace.
camshaft mod is a very efeective way to increase low and mid range -you have to say bye bye to kick starter.
carb is same as i told you roughly,only upjetting can do the trick,yes if a p 220 cam is used i suddegest a bigger jet then 180s or replace the carb to bs 32 aka p 220 carb.
crank shaft and cam shaft are 2 diff things,google it.

hope it clears up.

**princesirohi** · 02-15-2011, 05:49 PM

Originally posted by drvmtm View Post

why u r getting confused prince?

180 bore+piston is a direct fit without any change on head. got it
i told you to change valves because simple wire and tear till date with oem 150 s only,no upgread,just replace. ya ..understood this too
camshaft mod is a very efeective way to increase low and mid range -you have to say bye bye to kick starter. understood....but will decide upon discussion with my mechanic
carb is same as i told you roughly,only upjetting can do the trick,yes if a p 220 cam is used i suddegest a bigger jet then 180s or replace the carb to bs 32 aka p 220 carb. i will not replace the carb, only jet will be replaced. if someone can tell me jet size, it will be helpfull.
crank shaft and cam shaft are 2 diff things,google it. already googled last night....so its clear now.

hope it clears up.

now i need only two more things...

1) jet size.

2) how does cam help in increasing low and mid range torque.....is it by being high lift, valves are opened up more and for longer duration, so more fuel and air gets sucked in and is exhausted quickly too.

**drvmtm** · 02-16-2011, 01:43 AM

Originally posted by princesirohi View Post

now i need only two more things...

1) jet size.

2) how does cam help in increasing low and mid range torque.....is it by being high lift, valves are opened up more and for longer duration, so more fuel and air gets sucked in and is exhausted quickly too.

in a small word try first gen p 220 s jet,dont remeber the number though,the newer jets are smaller because of emmision norms.
yes its kinda like that only.

**NANOtechnology** · 02-16-2011, 01:57 AM

@ Doc

The first generation p220 was FI, didn't have jet.
if your talking about the first generation carb versions, then i think they are still running the same jet sizes.

@ all

I don't wish to create any confusion here, but i feel that going for bigger valves will not serve the purpose, as the port sizes and port curves will be left stock, high lift cam with bigger valves would not necessarily be better than the same sized valves.
cam can make a difference though, but technically it will make the revs climb faster, nothing more than that.

regarding reliability (since i am running big bore), i must admit, it won't really be like stock, the noise, vibes as well as the harshness will increase.
your bike will seem to be quite less reliable, as well as i have a doubt on the pulsar's crank bearings weather it will take the load.

Don't expect low end torque or midrange, they will go down than the stock, but higher revv punch will be unbeatable.

**reaperbabu** · 02-16-2011, 05:53 AM

I have been thru this quite a few times and would like to suggest you to just get the repairs done.

If you want a peppier 150 then..

1st oversize only if you have a skilled guy to bore and hone
exhaust port and combustion chamber polishing
Optional - Shave head by 0.25 mm (your timing chain might run lose though)
Use jets similar to 180 classic
K&N? zero benefit if not done right and negligble if done right
Get sprocketing done for acceleration...i have 18" spoke wheels but using sprocket set of 17" alloys

My bike is 6 yr old and done 64k kms but can out accelerate any 150 in its class...she tops out at 118kmph (true speed).
About the efficiency?!?! she returns 48kmpl when i do highway rides with an average speed of 75kmph and occasional burst to 100kmph.

So again...get into this only if you have practicle knowledge and know how to wrench..else just get her repaired change to new stock parts and she will last you another 15 to 20 thousand kms

All the best

**pavanchirmade** · 02-16-2011, 09:57 AM

Originally posted by NANOtechnology View Post

@ Doc

The first generation p220 was FI, didn't have jet.
if your talking about the first generation carb versions, then i think they are still running the same jet sizes.

Doc said P220S which is a carburetted bike man!
@ all

I don't wish to create any confusion here, but i feel that going for bigger valves will not serve the purpose, as the port sizes and port curves will be left stock, high lift cam with bigger valves would not necessarily be better than the same sized valves.
cam can make a difference though, but technically it will make the revs climb faster, nothing more than that.

Bigger valves with stock inlet sizes is pointless.
Cam shaft change will alter valve timings and overlap. This is necessary for the revs to climb faster and also better torque as the engine breathes better.Its not just the revs climbing faster.

regarding reliability (since i am running big bore), i must admit, it won't really be like stock, the noise, vibes as well as the harshness will increase.
your bike will seem to be quite less reliable, as well as i have a doubt on the pulsar's crank bearings weather it will take the load.

I too have the same worries. The crank can take the abuse. People are running very weird combinations on the pulsar.

Don't expect low end torque or midrange, they will go down than the stock, but higher revv punch will be unbeatable.

bro this will improve the lower end more than the top end.

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