Mid Range & Top speed loss in my Karizma - Please help

[redrage]

Hi Guys,

I Have a 2003 model Karizma which has clocked close to 30 K kms on date. I use the bike for city riding and normally long trips. I have serviced the bike at regular intervals and maintained it pretty well. My first modification for the bike was changing over to K&N airfilter (RC 1060) on which i experimented a lot, firstly removing the stock filter and plugging it in its place, this dint provide me any difference hence i mounted it directly to the Carb, removing the airbox completly. The revs were good but it wasnt really noticable in terms of performance. Then i wanted to upjet the bike learning that there wouldnt be any gains in performance riding the bike with stock jets. I got "convinced" by this certain mechanic who said he had got the right tools for upjetting the bike & wanted to work on my bike.He upsized the stock main jet, in a crude way. After completing work on the bike bike i rode it and it felt a little bit different but eventually i understood that he had made a mess of the main jet and bike was struggling. I added a free flow which i thought would help but that hasent either.

My pain problem now is the bike is slower than a stock Karizma ( I have compared it with my friends stock karizma) when it comes to top speed and midrange, the stock bike just vrooms past (even with me having filter,ffe etc what not). I brought the bike back to stock and again compared with similar results (Midrange, top end is bad). To add to my worries the mileage also is extremely poor (28 - 31 kmpl) compared to 35 - 38 Kmpl on my friends bike.My mechanic suggested i change the cam tensioner.I did. Please enlighten me whether this is the problem i dont have a good top end; beacuse with the old tensioner i feet nearing 7k rpm, i get a cut-cut sound and i felt like something was restricting the bike from revving beyond 7k. I have put back the filter and ffe and trying to work on it with a differnt mechanic. Hopefully i will get to compare it again with a stock karizma tommorow.

Please give me some inputs on which i can work on my bike.
Thank you guys.

[apachelongbow]

Originally Posted by redrage

Hi Guys,

I Have a 2003 model Karizma which has clocked close to 30 K kms on date. I use the bike for city riding and normally long trips. I have serviced the bike at regular intervals and maintained it pretty well. My first modification for the bike was changing over to K&N airfilter (RC 1060) on which i experimented a lot, firstly removing the stock filter and plugging it in its place, this dint provide me any difference hence i mounted it directly to the Carb, removing the airbox completly. The revs were good but it wasnt really noticable in terms of performance. Then i wanted to upjet the bike learning that there wouldnt be any gains in performance riding the bike with stock jets. I got "convinced" by this certain mechanic who said he had got the right tools for upjetting the bike & wanted to work on my bike.He upsized the stock main jet, in a crude way. After completing work on the bike bike i rode it and it felt a little bit different but eventually i understood that he had made a mess of the main jet and bike was struggling. I added a free flow which i thought would help but that hasent either.

My pain problem now is the bike is slower than a stock Karizma ( I have compared it with my friends stock karizma) when it comes to top speed and midrange, the stock bike just vrooms past (even with me having filter,ffe etc what not). I brought the bike back to stock and again compared with similar results (Midrange, top end is bad). To add to my worries the mileage also is extremely poor (28 - 31 kmpl) compared to 35 - 38 Kmpl on my friends bike.My mechanic suggested i change the cam tensioner.I did. Please enlighten me whether this is the problem i dont have a good top end; beacuse with the old tensioner i feet nearing 7k rpm, i get a cut-cut sound and i felt like something was restricting the bike from revving beyond 7k. I have put back the filter and ffe and trying to work on it with a differnt mechanic. Hopefully i will get to compare it again with a stock karizma tommorow.

Please give me some inputs on which i can work on my bike.
Thank you guys.

One thing redrage. Never try to make a bigger jet by drilling/re shaping your existing jet, it simply never works. Increasing performance is not so simple as rejeting the carb or adding a free flow to a single cylinder engine. it feels with your faulty upsized jet now, the bike simply dumps more fuel into the engine, and leads to higher unburnt fuel at high revs. You can verify this by checking the condition of your spark plug. Rejeting a carb is almost a fine art, and you need to visit an experienced mechanic for this. Also be aware that rejeting the carb, adding free flow, better air filter, might hardly give u a 0.5 bhp increase if at all, so not worth it.

One a karizma, one simple thing possible is to change the gearing by either a size smaller rear sproket or a one tooth higher front sproket, i believe the bike has enough torque to ensure a slightly better top end through this mod

[solly]

Are you running on stock tires or did you upsize?

[redrage]

Originally Posted by solly

Are you running on stock tires or did you upsize?

I am using 120 section tyres from MRF

[crazydiablo]

I would say bring it back to stock. Stock jets, stock filter and stock silencer. Probably take it to a authorized SS or a good mech and get it back to stock. While you mech played with your carbs maybe something has gone wrong.

Other than that,

1. change only one thing at a time
2. FFE is pretty much useless
3. Filter should be done with proper upjetting. Jet should not be crudely drilled.

[praJEEP]

[quote=crazydiablo;593417]I would say bring it back to stock. Stock jets, stock filter and stock silencer. Probably take it to a authorized SS or a good mech and get it back to stock. While you mech played with your carbs maybe something has gone wrong.

i second your words dude,
@red bring the bike back to stock
i have pm'ed you.

[redrage]

Originally Posted by crazydiablo

Filter should be done with proper upjetting. Jet should not be crudely drilled.
I would say bring it back to stock. Stock jets, stock filter and stock silencer. Probably take it to a authorized SS or a good mech and get it back to stock.

Any place you reccomend does this job properly? I have tried and i havent come across 1 mechanic who has confidently said he will upjet a karizma.

Originally Posted by crazydiablo

I would say bring it back to stock. Stock jets, stock filter and stock silencer. Probably take it to a authorized SS or a good mech and get it back to stock.

Even after i tried on the stock jets, stock filter, stock silencer, I found it slower than another karizma( stock) . This is my main worry, so i started this thread. I am lamenting that even after i tried getting the bike back to stock it dint give me any results, so i thought heck with it and bolted everything back.

[extreme_torque]

Originally Posted by redrage

Even after i tried on the stock jets, stock filter, stock silencer, I found it slower than another karizma( stock) . This is my main worry, so i started this thread. I am lamenting that even after i tried getting the bike back to stock it dint give me any results, so i thought heck with it and bolted everything back.

Did you switch riders while comparing performance?

[redrage]

Originally Posted by extreme_torque

Did you switch riders while comparing performance?

Yes, We tried that as well. My bike seems to be losing out after higher 2nd , 3rd & 4th gears in midrange , bike is not able to cross 122 - 123 kmph on the speedo where the stock bike clocks about 140kmph (125 true speed).

[Technocrat]

Most of the points have been covered by people. But one note I would like to make is that 28-31kpl is nota bad mileag for ZMA all those who claim higher are either lying or ride very sedately. The max in sedate riding that you can get is 35kpl

[redrage]

Originally Posted by Technocrat

Most of the points have been covered by people. But one note I would like to make is that 28-31kpl is nota bad mileag for ZMA all those who claim higher are either lying or ride very sedately. The max in sedate riding that you can get is 35kpl

Techno you had a karizma right? Do you think the camtensioner has anything to do with the bike not able to rev freely?

About the mileage part when i rode with my friend on his 10 k logged karizma, he got a comfortable 38 - 40 on the highway where i could manage only 32

[doomsday]

Originally Posted by redrage

Do you think the camtensioner has anything to do with the bike not able to rev freely?

The only issue you will face because of a faulty tensioner is rough low speed operation. The idling will not be stable as well. Also did you change your cam chain while changing the tensioner or just the tensioner? Ensure that you change the cam chain also since a used chain with a new tensioner will wear out the tensioner much sooner. (something like chain sprockets)

Make sure that the main AND the pilot jets are back to stock sizes. Get the carb disassembled and cleaned and check the carb slide for damages. Once you set up the carb and tune it, ride the bike for some kilometers and check the spark plug. The tip should be brownish in colour. If this is the case, it means your carburetion is perfect.

Moving on then, get your clutch plates inspected as well. Replace if they are worn out (which might be in case you are running on the first set). Also check the sprockets and replace if they have worn out (which might be in case you are running on the first set)

Lastly check your front disc assembly and ensure that the plate is in shape and the pads are not grinding against the plate even though there is no pressure on the lever. (I know it sounds overboard but this happened in my case). Change the disc place if its bent; dont be convinced by someone who says he can re-surface it.

Hope this helps.