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cb360t carb

Posted: Mon Feb 16, 2009 9:40 am
by Fargo360
I'm rebuilding the carbs on my bike after the poor performace of last year. I noticed that there are some jets up by the diaphram, on one carb they screw out, on the other they don't. Is it possible that I have two carbs from two different bikes? How do I get those jets that don't screw out, out?

Posted: Tue Feb 17, 2009 1:29 pm
by honda750
i would seriously doubt that you have 2 different carbs, although that would of course explain the poor performance last year, and as for getting them out you're going to just have to muscle them out.

use carb cleaner and/or wd40 and the largest possible screwdriver. they're most likely brass so be careful to not strip them.

im afraid that's all i got haha good luck

Posted: Wed Feb 18, 2009 9:23 am
by coffee_brake
If the jet doesn't have a slot for a screwdriver, or a place for a wrench to fit, it probably is pressed in and isn't supposed to come out.

If it is supposed to come out but it's just stuck, a hand-held impact wrench and a vise to hold the carb can work wonders if used carefully.

Also heat. One of those propane torches, heat up the area real good (yeah you know not to get the flame near fuel, right? Boom and all?) and then use the impact on the hot jet...it's worked for me several times.

Posted: Wed Feb 18, 2009 5:16 pm
by Fargo360
well, the jets for the right carb had screw notches in them, so I just screwed them out and they came out just fine. The jets in the left carb did not have screw notches in them. I'm not too worried about it in the long run, everything else was the same as far as main, pilot, slow jets down by the bowl. It was just those jets up in the diaphram area that made me wonder. I don't know, how often do you find carbs that on one carb the jets come out one way, and on the other carb they come out a totally different way?

If the carbs are off of two different bikes, will I have trouble sync'ing them?

Posted: Thu Feb 19, 2009 5:35 am
by coffee_brake
Wow. sounds weird. Really need some pics at this point, can you get some pics posted?

Posted: Thu Feb 19, 2009 8:52 am
by Fargo360
In the pic they are lined up like they would be on the bike (left/left - right/right). The one on the right has screw out jets on top and the one one the left has pressfit jets on top.

Image

Image

Image

The pics aren't that great but I hope you can get an idea of what i'm talking about. I'm just worried that I have carbs off of two different bikes, and that might make sync'ing them a bugger.

Posted: Thu Feb 19, 2009 10:13 am
by Wrider
I've never heard of that before but it could simply be a way to adjust how well the diaphragm on the adjustable one raises and lowers, which would adjust throttle sensitivity to a rider's preference.
If you only changed one it would affect the engine's sensitivity to throttle inputs but not enough to kill the performance.

As far as syncing them, the only way it would make a difference with those jets is when you're above idle or continuously adjusting the throttle if I'm thinking about it right.

Posted: Thu Feb 19, 2009 11:47 am
by honda750
im empty on ideas so this is the only help i might provide:

http://www.bikebandit.com/houseofmotorc ... 4sch398835

(i picked '75 cuz its a popular year for them, but just go to the bikebandit site and OEM parts and click year, etc, to get your bike specifically, although there will be really no differences between years i would bet)

Posted: Mon Feb 23, 2009 5:57 pm
by Fargo360
So, I'm going to sync my carbs. I've never done this before so I'm not really sure what I'm doing. Where am I supposed to plug the monometers? Then, what exactly am I tuning?

Posted: Mon Feb 23, 2009 7:10 pm
by Wrider
Can you link to the monometers you're using? As for the vacuum lines it's hard to describe without pictures, but I found this article that should help.
http://www.motorcyclistonline.com/howto ... index.html
Don't be ashamed to ask any questions, even ones you may think are stupid or easy, syncing carbs is vital and hard to learn without someone there to help you IMHO.