Carb Questions...

[bighamms]

1981 gs450s.....
2 carb setup.....(not sure of model/style)


after submitting a few threads in an attempt to get my bike running, it became obvious that my methodology was a bit off. Like most newbies, I just want to ride. So after some advice from members, i've decided to slow down, and do it right. First step, CARBS. I opened them up and cleaned them when I first got the bike, but am now committing myself to a rebuild (o-rings, gaskets, jetting (which i'll explain later)). So i have some questions. Let me preface the questions by saying that I'm asking because I don't know, regardless of how simple or common sense they may seem. I'm planning to use the barryman's carb dip.

1. is it ok to use the dip several times
2. Aside from rubber and plastic, can ALL metal piece take the barryman bath (ie, nuts, bolts, washers, brass, bowls, bodies, spring, jets, knobs, etc. you get the point)
3. should both carbs have the same mains & pilots (i am asking because I discovered that 1 carb had a 115/17.5 and the other had 120/20. Seems weird, but thought I would verify).
4. Should both carbs have plugs (neither of them currently have plugs installed)
5. If plugs are required, do they go over the mains or the pilots
6. On my carbs, the mains/pilots are located in the float bowl, but i do not recall seeing an AIR SCREW
7. Upon reassembly, where might i find the proper setting for the jets

I did take the time to read/review the carb cleanup series on this site. but because my carbs differ from those in the illustration, i wanted to make sure I was clear before proceeding.

thanks in advance.
rob

 

[bighamms]

and the forum goes silent.... WOW! NOTHING? Somebodies has to know the answer to some of these questions.

 

[hampshirehog]

1. Yes
2. Yes
3. Yes - both the same.
4.No - not shown in the parts diagram
5. See 4 above
6. The pilot air jet sits on the airbox side of the carb. Size given is 1.6. No airscrew in the parts diagram.
7. 115 mains / 17.5 pilots is the standard set up for your bike.

 

[bighamms]

@hamshirehog....Thanks mate. Exactly what I needed. I do just have other question regarding jets....where is the best place to purchase online. Checked ebay, but want to make sure I get the good stuff.

 

[hampshirehog]

@hamshirehog....Thanks mate. Exactly what I needed. I do just have other question regarding jets....where is the best place to purchase online. Checked ebay, but want to make sure I get the good stuff.

I'm in the UK and get all my carb bits from these guys:
http://www.allensperformance.co.uk/

Pass on what the postage is to the US but their service is first class.

 

[BassCliff]

Hi,

You bike has Mikuni BS32SS carbs. There is more general information on my website.

Carb Specs: Float Height/Jetting/Tuning​

Carb Notes: Synchronizing/Troubleshooting/Theory

From your "mega-welcome":

Sudco International - Carburetor parts, Classic & Late Model Replacement & Performance Parts, etc.
http://www.sudco.com/ (http://www.sudco.com/oemcarbparts.html)
MotorcycleCarbs.com - Carburetor parts, etc.
http://www.motorcyclecarbs.com/index.cfm
Jets R Us - Carburetor parts, filters, gauges, etc.
http://www.jetsrus.com/
Parts'n'More - Classic UJM parts (i.e. gasket sets): $35 minimum, $5 shipping to lower 48
https://www.partsnmore.com/

There is no "air screw" on the BS carbs. There is one "mixture screw" used to adjust the fuel/air mixture at idle. Turning it out (counter-clockwise) richens the mixture at idle.

You may have to remove the caps to uncover the mixture screws.

I don't have any 450-specific information for you, but there is a manual for your bike on my website. Please help yourself.


Thank you for your indulgence,

BassCliff


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