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The 78 jet would be where the 90 goes, and the 120 goes where the 112 is.



 

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Discussion Starter · #3 ·
Awesome.I just got her back together after getting rid of that airbox and it runs like crap, rejetting tomorrow.Thanks!
 

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You may need more than a simple rejet. These are CV carbs and rely a lot on the air flow restriction of the air box. I don't even think you hit the main jet until piston is about 3/4 up. So if the vaccuum isn't there to lift the piston a rejet is useless.



Hopefully it works for you. Let us know how it works out. A lot of us run w/out the airbox.
 

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If you're feeling dangerous,



The main thing is to keep it straight. If you have a good setup/machine shop, you could make a jig to drill jets.



(Width = true hole diameter)

Width------Keihin # -- DynoJets # -- Mikuni #

0.0350---- 92.5--------- 92---------- 86.3

0.0360---- 95----------- 94---------- 88.1

0.0370---- 97.5--------- 96---------- 90.0

0.0380---- 100---------- 98---------- 91.9

0.0390---- 102.5------- 100---------- 93.8

0.0400---- 105--------- 102---------- 95.6

0.0410---- 107.5------- 104---------- 97.5

0.0420---- 110--------- 106---------- 99.4

0.0430---- 112.5------- 108--------- 101.3

0.0440---- 115--------- 110--------- 103.1

0.0450---- 117.5------- 112--------- 105.0

0.0460---- 120--------- 114--------- 106.9

0.0470---- 122.5------- 116--------- 108.8

0.0480---- 125--------- 118--------- 110.6

0.0490---- 127.5------- 120--------- 112.5

0.0500---- 130--------- 122--------- 114.4

0.0510---- 132.5------- 124--------- 116.3

0.0520---- 135--------- 126--------- 118.1

0.0530---- 137.5------- 128--------- 120.0

0.0540---- 140--------- 130--------- 121.9

0.0550---- 142.5------- 132--------- 123.8

0.0560---- 145--------- 134--------- 125.6

0.0570---- 147.5------- 136--------- 127.5

0.0580---- 150--------- 138--------- 129.4

0.0590---- 152.5------- 140--------- 131.3

0.0600---- 155--------- 142--------- 133.1

0.0610---- 157.5------- 144--------- 135.0

0.0620---- 160--------- 146--------- 136.9

0.0630---- 162.5------- 148--------- 138.8

0.0640---- 165--------- 150--------- 140.6

0.0650---- 167.5------- 152--------- 142.5

0.0660---- 170--------- 154--------- 144.4

0.0670---- 172.5------- 156--------- 146.3

0.0680---- 175--------- 158--------- 148.1

0.0690---- 177.5------- 160--------- 150.0

0.0700---- 180--------- 162--------- 151.9

0.0710---- 182.5------- 164--------- 153.8

0.0720---- 185--------- 166--------- 155.6

0.0730---- 187.5------- 168--------- 157.5

0.0740---- 190--------- 170--------- 159.4

0.0750---- 192.5------- 172--------- 161.3

0.0760---- 195--------- 174--------- 163.1

0.0770---- 197.5------- 176--------- 165.0

0.0780---- 200--------- 178--------- 166.9

0.0790---- 202.5------- 180--------- 168.8

0.0800---- 205--------- 182--------- 170.6

0.0810---- 207.5------- 184--------- 172.5

0.0820---- 210--------- 186--------- 174.4

0.0830---- 212.5------- 188--------- 176.3

0.0840---- 215--------- 190--------- 178.1

0.0850---- 217.5------- 192--------- 180.0

0.0860---- 220--------- 194--------- 181.9

0.0870---- 222.5------- 196--------- 183.7

0.0880---- 225--------- 198--------- 185.6

0.0890---- 227.5------- 200--------- 187.5
 

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Jetsrus.com have these so cheap you would spend more on the drill bit unless you have access to a good machine shop. Plus edge condition of the orifice is so important. I'd really recommend jetsrus.com - no affiliation, just a happy customer.
 

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Discussion Starter · #12 ·
So I hooked up the 90/120 jets and slapped on some pods. It's still got the h-box and stock pipes minus the megaphones. It runs pretty stout actually.If the choke is fully open she will stumble slightly, but it goes away after riding for about 30 minutes. I feel like I need to do some more tuning on them but it pulls alot harder now and I love it.Now I need to replace my dying clutch and I'll def. be in business.
 

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Discussion Starter · #15 ·
I got my jets from a local Honda Store. They had my jets at 5 bucks a piece.I got them for 4.25 a piece since I'm a volunteer fireman(flashed the badge,lol).
 

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What do you mean by 'damage'? if you mean "require a jetting change" the answer is that it depends on what you replace the stock mufflers with. If the new mufflers flow differently than the old ones did, then a rejet will be required.



Note, also, that everything in the exhaust system rusts together. Removing the pipes without damaging the H box is quite doable, but usually not easy.
 

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What do you mean by 'damage'? if you mean "require a jetting change" the answer is that it depends on what you replace the stock mufflers with. If the new mufflers flow differently than the old ones did, then a rejet will be required.



Note, also, that everything in the exhaust system rusts together. Removing the pipes without damaging the H box is quite doable, but usually not easy.


Mine came off ok. No damage.
 

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Are u goin to just remove the H box? If so ur still goin to have to re jet. You are going to be removing the back pressure. Do u plan on puting any mufflers on?
 
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