Topic: 75 550 running a bit lean on 1-3

[hellraiserDLX]

I just got the bike back together after cleaning the carbs and replacing jets back to factory.  Factory airbox minus the lid. I rode it for about ten minutes and pulled the plugs and 1-3 were kinda white and 4 looked good. Would synching the carbs better this at all or would bumping the main jet up be the best option? Ill try to post a pic of What the plugs in 1-3 look like

[TwoTired]

Why would you avoid vacuum syncing 4 independent carbs on a 4 cylinder engine?

[dave500]

get your ignition spot on then sync the carbs,so long as youve cleaned them properly including the emulsion tubes and the floats are all equal and the air filter is good,not just look good but good,itll be fine,make sure you have no vacuum leaks in the rubbers aswell.

[hellraiserDLX]

Why would you avoid vacuum syncing 4 independent carbs on a 4 cylinder engine?

nobody said anything about avoiding synching four independent carburetors on a four-cylinder engine bud. I was simply asking because for one I don't know in 2 if I had the capabilities of synching them right away I would. Tews offered to help me out but he is a pretty busy huy and I'm just looking for more knowledge.

[hellraiserDLX]

I just wanted to know if I should put bigger jets in there right away before synching them and wasting somebody else's time.

[hellraiserDLX]

get your ignition spot on then sync the carbs,so long as youve cleaned them properly including the emulsion tubes and the floats are all equal and the air filter is good,not just look good but good,itll be fine,make sure you have no vacuum leaks in the rubbers aswell.

Thanks for the info.  I have brand new ngk plugs and wires.  The air filter is brand new as well. I will diuble check for leaks with the rubbers as well

[mono]

Why would you avoid vacuum syncing 4 independent carbs on a 4 cylinder engine?

nobody said anything about avoiding synching four independent carburetors on a four-cylinder engine bud. I was simply asking because for one I don't know in 2 if I had the capabilities of synching them right away I would. Tews offered to help me out but he is a pretty busy huy and I'm just looking for more knowledge.

Yeah, it's best to always clean and sync them 1st - go through them per the manual (download one if you don't have a service manual) and make sure everything's all super clean and the needles are all in the same position and the floats are all set correctly (22mm i think?).  If you've done some of this already, just check the steps you may have skipped!  a good bench sync takes a little patience but should get you running pretty smooth if you do it carefully.

[hellraiserDLX]

I did everything you said there besides the bench synch. She runs like a champ. Fires first crank idles smooth with no stumbles. I'm just a bit worried about running it too lean is all. Thank you for the tips

[Tews19]

Hellraiser... I am free around 1130 for about an hour.. call me. And you can swing by

[mono]

the bench sync will probably help then -- you'll have to pull the carbs, of course, but it should help get you closer to perfect.  if it's running OK overall, i guess it's up to you whether to do that before you can get access to the vacuum sync or not, but it will help make vaccuum syncing easier.

why are you worried about running lean?  do you have to leave it choked a little to run well?    also, have you adjusted your air mixture screws on the side of the carbs?   lol sorry lots of ?s but it's all important!

[mono]

Hellraiser... I am free around 1130 for about an hour.. call me. And you can swing by

^^ Or that!  Good lookin out, Tews.

[hellraiserDLX]

Hellraiser... I am free around 1130 for about an hour.. call me. And you can swing by

unfortunately I'm working until 530 or 6 o'clock tonight. I'm off all weekend though if any time works for you. Pm me your number if you want. Ill send you mine.

[lucky]

I just got the bike back together after cleaning the carbs and replacing jets back to factory.  Factory airbox minus the lid. I rode it for about ten minutes and pulled the plugs and 1-3 were kinda white and 4 looked good. Would synching the carbs better this at all or would bumping the main jet up be the best option? Ill try to post a pic of What the plugs in 1-3 look like

A 10 minute ride is not enough to make any decision on.

[dave500]

if the manifolds havent been off the heads in a while theres a fair chance the o rings there have flattened and may leak a little air,its common,i like to flatten the manifold surface on a flat glass with wet or dry paper,this also improves the crush on the new o rings very slightly,the carbs are a fiddle to get on and off so do all you can to everything if you do remove them.