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okay.. well my mc19 has been sitting in my garage for about 3 weeks to a month. ive had the plugs out for about 2 weeks, and im planning on getting it running again this week. i have ordered size 115 jets as i have an aftermarket exhaust and uni filter, but im not sure of what i would need to do when cleaning the carbs and doing this 115 size jet modification. ive looked for the thread to find out what i need to do but i cant find it anywhere.! if anyone has any other suggestions on what else to do that would be appreciated, i plan on changing the sparks, cleaning the carbs, rejetting and balancing them, not sure what else id need to do? cheers guys.
 
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francisz said:
okay.. well my mc19 has been sitting in my garage for about 3 weeks to a month. ive had the plugs out for about 2 weeks, and im planning on getting it running again this week. i have ordered size 115 jets as i have an aftermarket exhaust and uni filter, but im not sure of what i would need to do when cleaning the carbs and doing this 115 size jet modification. ive looked for the thread to find out what i need to do but i cant find it anywhere.! if anyone has any other suggestions on what else to do that would be appreciated, i plan on changing the sparks, cleaning the carbs, rejetting and balancing them, not sure what else id need to do? cheers guys.
but some needle washers, you will need about 12x 0.2mm thick
 

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would that mean id need to put 4 washers under each needle? what about pilot screw settings? im gonna get my carbs balanced at the shops cause i got quoted only 50 bucks. so that doesnt matter but i want to know what settings i should have the mixture screws at roughly. Also, ive heard that some jets on the carbs are diferent sizes, like some are like two are liek 90 something and two are like 105..? if i change them all to 115 jets and put washers under the needles, would it be all sweet? cheers!
 

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it is not always going to be a simple 'pop the jets and a few washers in and off you ride with a super powerful bike' situation.

Firstly what are you hoping to achieve? more power or just a bike which runs smoothly? I haven't ridden a bike with bigger jets in it, I would love to so I could see if it is a noticeable as people seem t say it is though. might be worth getting in touch with the dude who built that rcv replica as he used an mc19 engine and carbs with 115 jets in them, he should be able to tell you what works.
 
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francisz said:
would that mean id need to put 4 washers under each needle? what about pilot screw settings? im gonna get my carbs balanced at the shops cause i got quoted only 50 bucks. so that doesnt matter but i want to know what settings i should have the mixture screws at roughly. Also, ive heard that some jets on the carbs are diferent sizes, like some are like two are liek 90 something and two are like 105..? if i change them all to 115 jets and put washers under the needles, would it be all sweet? cheers!
erm... 2 jets are 102's and 2 are 105's on the jap models. think 112's on the aussie but not sure. you need 2-3 additional washers under each needles, so thats a total of 3-4 but you will have to experiment with it. you will have to play with idle a bit, but if you are getting your carbs balanced they will probably get mixture correct for you too won't they? i used 2 turns out and it was pretty good (jap model). Can't tell you if it will be all sweet, you will have to get your hands dirty and play around a bit....
 

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post your progress!
I'm considering doing this as well, I'll be glad to let you make the mistakes first =P
 
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banana.logic said:
it is not always going to be a simple 'pop the jets and a few washers in and off you ride with a super powerful bike' situation.

Firstly what are you hoping to achieve? more power or just a bike which runs smoothly? I haven't ridden a bike with bigger jets in it, I would love to so I could see if it is a noticeable as people seem t say it is though. might be worth getting in touch with the dude who built that rcv replica as he used an mc19 engine and carbs with 115 jets in them, he should be able to tell you what works.
To be honest, completely honest, I think the noise and ease of starting and placebo affect is better than the gain :p runs smoothly though :)
 

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Discussion Starter #8
will do this. i want to get my bike running nice and smooth. so i will play around with it a bit. seems a bit tedious to take the carbs apart constantly but ill start off with about 3. will get back to this and tell you how it goes! hopefully it gets my bike running smoother than it is now. how did you get your done roobars? did you just add jets and a few washers? and played around with it? anything else you do to it?
 
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francisz said:
will do this. i want to get my bike running nice and smooth. so i will play around with it a bit. seems a bit tedious to take the carbs apart constantly but ill start off with about 3. will get back to this and tell you how it goes! hopefully it gets my bike running smoother than it is now. how did you get your done roobars? did you just add jets and a few washers? and played around with it? anything else you do to it?
I cleaned and balanced them, and put in a new seal kit that I got from studricho. They looked barnd new and shiny. I like shiny things :)

try the old forum for fatty's tuning guide. everything is there except the frustrations, and mistakes.
 

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Discussion Starter #11
viper33 said:
http://cr-xorg.readyhosting.com/cbr250/forum/topic.asp?TOPIC_ID=26849

fatty's cbr tuning guide
might be helpful
far! cheers man was looking for this for ages!
 

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roobars said:
francisz said:
would that mean id need to put 4 washers under each needle? what about pilot screw settings? im gonna get my carbs balanced at the shops cause i got quoted only 50 bucks. so that doesnt matter but i want to know what settings i should have the mixture screws at roughly. Also, ive heard that some jets on the carbs are diferent sizes, like some are like two are liek 90 something and two are like 105..? if i change them all to 115 jets and put washers under the needles, would it be all sweet? cheers!
erm... 2 jets are 102's and 2 are 105's on the jap models. think 112's on the aussie but not sure. you need 2-3 additional washers under each needles, so thats a total of 3-4 but you will have to experiment with it. you will have to play with idle a bit, but if you are getting your carbs balanced they will probably get mixture correct for you too won't they? i used 2 turns out and it was pretty good (jap model). Can't tell you if it will be all sweet, you will have to get your hands dirty and play around a bit....
Just to avoid confusion, the OP has an MC19, which do not have 102's and 105's but 90's or something along those lines.

Just so he doesn't open it up and shit himself looking for them.
 
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