How to balance your carbs

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AMCQ46
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Re: How to balance your carbs

Post by AMCQ46 » Wed Sep 24, 2014 11:14 am

2600rpm in 5th or 6th is not something these big V2's like. it will be lumpy as hell if you try that, so it sounds like your bike is normal.
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Wicky
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Re: How to balance your carbs

Post by Wicky » Wed Sep 24, 2014 11:27 am

True dat luggin it at low revs in high gears will test the transmission. Use the gearbox supplied by Honda and if you really want to lug it along check the cush drive rubbers and chain tension are all tip top.
It may be that your whole purpose in life is simply to serve as a warning to others.

Bikermort
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Re: How to balance your carbs

Post by Bikermort » Fri Sep 26, 2014 11:08 am

I rode my mates today and his is definately smoother. He noticed the roughness of mine too. Its not really bad but is enough to notice. Think compression test is next step.
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NZSpokes
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Re: How to balance your carbs

Post by NZSpokes » Fri Sep 26, 2014 12:03 pm

Bikermort wrote:I rode my mates today and his is definately smoother. He noticed the roughness of mine too. Its not really bad but is enough to notice. Think compression test is next step.
Wont be compression. Whats your fuel screw setting? Any puss of black smoke? Whats your jetting? How is the air filter? Whats the output on your TPS?

Do the basics first.

And its not a car, give it some revs.

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Re: How to balance your carbs

Post by Bikermort » Fri Sep 26, 2014 11:21 pm

NZSpokes wrote:
Bikermort wrote:I rode my mates today and his is definately smoother. He noticed the roughness of mine too. Its not really bad but is enough to notice. Think compression test is next step.
Wont be compression. Whats your fuel screw setting? Any puss of black smoke? Whats your jetting? How is the air filter? Whats the output on your TPS?

Do the basics first.

And its not a car, give it some revs.
Im giving it some no worries there. You can feel it through the rev range. No smoke, air filter good. TPS havent checked that? I know what they do on fuel injection...not carby though? will have to look that up. Havent touched fuel screw settings. It doesnt feel like it bogs down at all and still make plenty of power just rough.

Starts easy enough every time so not thinking valves. Still think its some sort of balance problem be it carbs or compression?
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tony.mon
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Re: How to balance your carbs

Post by tony.mon » Fri Sep 26, 2014 11:31 pm

AMCQ46 wrote:2600rpm in 5th or 6th is not something these big V2's like. it will be lumpy as hell if you try that, so it sounds like your bike is normal.
Agreed- what were you thinking?
You should be in 5K in fourth then, just picking up nicely.

Stir it up ((c) Bob Marley)
It's not falling off, it's an upgrade opportunity.

Bikermort
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Re: How to balance your carbs

Post by Bikermort » Sat Sep 27, 2014 1:31 am

tony.mon wrote:
AMCQ46 wrote:2600rpm in 5th or 6th is not something these big V2's like. it will be lumpy as hell if you try that, so it sounds like your bike is normal.
Agreed- what were you thinking?
You should be in 5K in fourth then, just picking up nicely.

Stir it up ((c) Bob Marley)
What was i thinking? I was thinking im riding to work and cruising at about 80km/hr.
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NZSpokes
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Re: How to balance your carbs

Post by NZSpokes » Sat Sep 27, 2014 8:22 am

Bikermort wrote:
NZSpokes wrote:
Bikermort wrote:I rode my mates today and his is definately smoother. He noticed the roughness of mine too. Its not really bad but is enough to notice. Think compression test is next step.
Wont be compression. Whats your fuel screw setting? Any puss of black smoke? Whats your jetting? How is the air filter? Whats the output on your TPS?

Do the basics first.

And its not a car, give it some revs.
Im giving it some no worries there. You can feel it through the rev range. No smoke, air filter good. TPS havent checked that? I know what they do on fuel injection...not carby though? will have to look that up. Havent touched fuel screw settings. It doesnt feel like it bogs down at all and still make plenty of power just rough.

Starts easy enough every time so not thinking valves. Still think its some sort of balance problem be it carbs or compression?
Does sound like a TPS thing. Its on the RH side of your carbs. Plenty of how tos on adjusting it.

Bikermort
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Re: How to balance your carbs

Post by Bikermort » Sat Sep 27, 2014 9:29 am

Thanks for that mate. Ill give it a go.
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kenmoore
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Re: How to balance your carbs

Post by kenmoore » Sat Sep 27, 2014 9:51 am

Check your TPS and do the Bernie Morgan air filter mod, that will help it smooth out.
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dudehog
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Re: How to balance your carbs

Post by dudehog » Tue Sep 30, 2014 4:31 pm

Hi, sorry to revive an old thread but I do have a question.
Reading the honda service manual it says the difference in vac between the front and rear is 0.8 inMg.
Now does this mean the front has a bigger pull than the rear or the other way around?
for example: (random vac numbers rounded to 1 inMg)
FRONT WITH A STRONGER VAC:
Front = -25 inMg
Rear = -24 inMg

OR

REAR WITH A STRONGER VAC:
Front = -25 inMg
Rear = -26 inMg

I'll be doing me first carb balance with this so want to get it right and this thread is far more helpful than the service manual so thank you :Beer1:

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AMCQ46
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Re: How to balance your carbs

Post by AMCQ46 » Tue Sep 30, 2014 4:40 pm

no its just setting it so the difference is no greater than 1
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dudehog
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Re: How to balance your carbs

Post by dudehog » Tue Sep 30, 2014 4:41 pm

sweet. I'll try to get it as close to 0.5 inMg difference as possible. gives me a 0.3 tolerance :)

Bikermort
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Re: How to balance your carbs

Post by Bikermort » Wed Oct 01, 2014 12:05 am

kenmoore wrote:Check your TPS and do the Bernie Morgan air filter mod, that will help it smooth out.
Adjusted my TPS today. I did it by just removing the seat and probing the wires at the ignition module. Was able to get at the TPS easy enough with the seat off too. It was at 758ohms. Have adjusted it to 500. Haven't gone for a ride yet only started it and it does seem to idle smoother. Riding into work in a couple of hours so will see how it goes.

And i did the airfilter mod too :D
Yamaha IT175
Honda CB900F 82
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Bikermort
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Re: How to balance your carbs

Post by Bikermort » Wed Oct 01, 2014 1:44 pm

TPS and air filter mod made a notable difference. Thanks to all those that provided useful advice!

Cheers
Yamaha IT175
Honda CB900F 82
Yamaha YZ250 03
Yamaha XT600e 03
Honda VTR1000 03

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