Carb teardown, clean and rebuild

[nogrey]

Hey all. I just recently finished a carb sync and pilot adjust using the Digi Sync. Everything went like clockwork and all seemed to come in as expected. Problem is, I'm still not ecstatic about the way my '97 runs. This is going to be a tough one because I have a few things bouncing around my head that I can't get settled. You see, I know the '97 has a slightly different cam than all the others. So is that why at idle it has sort of an uneven feel to it? It's not popping on decel, and the throttle response is smooth enough, it just doesn't seem as snappy as it should be. I've ridden many, many Valks. Some got it, some don't. My '97 just doesn't seem to be "there" yet. I'm considering a carb tear down, clean and renew using all new seals, gaskets etc. I have #38 jets because it was suggested a couple of years ago as a resolution to my idle and decel issues that some thought were caused by the K&N filter and cut piggies causing a little different back pressure and intake pressure issue. My bike has been desmogged, so should not be any vacuum issues. Just not sure what else to do to bring the girl to her desired strength. She's only got 10K miles on her.
Do I need to replace the floats? I have new float valves, gaskets etc.
Should I go back to #35 slow jets?
I know I could take it to Big BF or Attic Rat and they'd perform their magic, but until I have more $$$ I really can't afford to do that. Plus, I'd like to fix her myself if I can.
Thanks for your observations,
Greg

[The emperor has no clothes]

A '97 with only 10k has spent a lot of time just sitting. I think a thorough cleaning of the carbs is in order. I also see no reason not to put in the new floats and needles. As to slow jet size, I don't know.

[Pete]

Nothing runs as well as clean carbs and new air cleaner.

If it is not performing right and idling smooth, then cleaning and servicing the carbs is a good place to start.

You indicated that you have modded exhaust and air filter. So you need to check yous spark plugs for an indication of whether you are running rich or lean. Or have someone do an exhaust gas test for lean/rich.

If all is well I would stay with the 35's, if lean on the test then 38's and perhaps 1 step on the main jets.

You can help response some by installing Interstate carb springs and/or and Interstate spark controller. These two items are not true fixes for problems but small enhancements.

Good luck.

[nogrey]

A '97 with only 10k has spent a lot of time just sitting. I think a thorough cleaning of the carbs is in order. I also see no reason not to put in the new floats and needles. As to slow jet size, I don't know.

I should have noted that I bought the bike with 2500 miles on it a few years ago. A honda (reputable/knowlegable) mechanic went through the carbs. It has not set much since then.

[Hooter]

Just my 2 cents...FWIW...by description I see no reason to tear it down.  Idle is smooth, acceleration is the same and no popping or back firring on decel. Not to mention the sync went well indicates things should be right.


I used to take a clean white rag and drain a carb into it. If crap came out on the rag,  a cleaning or rebuild could be considered. With all the good outcome you've had so far, I'd ride it.

[jim@98valkyrie.com]

I used copious quantities of Berrymans B-12 to clear the junk out after this one sat for about two years.

[nogrey]

Just my 2 cents...FWIW...by description I see no reason to tear it down.  Idle is smooth, acceleration is the same and no popping or back firring on decel. Not to mention the sync went well indicates things should be right.


I used to take a clean white rag and drain a carb into it. If crap came out on the rag,  a cleaning or rebuild could be considered. With all the good outcome you've had so far, I'd ride it.

That is why I asked. I really need a good opinion. Thanks.

[Savago]

10K? The engine is still breaking in.
:-D

Put some serious hard miles on it (e.g. 3000 miles in 2 weeks) and she will be happy.

[98valk]

not all '97s have different cams.  I've found 49 state '97s with emission cams.

38s and larger main jets are too rich unless after market exhaust (larger head pipes) and air box mods.

there will be a better snappier throttle and response with stock 35s with mixture screws opened up to 2 to 3 turns open.

only run regular gas.
as mentioned run a few cans of B12.  then always run fuel valve cleaners with the new PEA formulation of cleaners.

[Brian]

My 97 idles much smoother after the last time I went thru the carbs. This last time I took the pilot screws out and cleaned those passages real well. I did not do this exercise previously. Redeye sells the kits and the tool to remove these. I really think this helped my idle as it was erratic before. I have 30,000 miles in mine.  

[jim@98valkyrie.com]

If you end up tearing them down, use an ultrasonic cleaning machine to get crud out of all of the nooks and crannies. As far as a chemical goes, I use Krud Kutter Parts Cleaner. Heard many others work too, but this is the one that gets rid of those nasty green deposits.

[nogrey]

10K? The engine is still breaking in.
:-D

Put some serious hard miles on it (e.g. 3000 miles in 2 weeks) and she will be happy.

When I bought it (in Florida) it had 2500 miles on it. I rode it from there to Idaho in 4 days. 3300 miles. We rode pretty hard every day all day long. She just needs......somthing! I don't know what. I have been accused of being OCD...

[nogrey]

not all '97s have different cams.  I've found 49 state '97s with emission cams.

38s and larger main jets are too rich unless after market exhaust (larger head pipes) and air box mods.

there will be a better snappier throttle and response with stock 35s with mixture screws opened up to 2 to 3 turns open.

only run regular gas.
as mentioned run a few cans of B12.  then always run fuel valve cleaners with the new PEA formulation of cleaners.

Really good info here. I still have the old 35's that came out. Probably should get a new set. I'll get a few cans of B12. I have been running only non-ethanal regular, 87 octane through her unless I'm on a road trip and can't get it.  Any way I can find out what cam mine has in it? She was number 886 off the assembly line in '96. I'll have to look into the PEA formula thing. I don't really know that much about additives. I'm guessing they would be present in top tier fuels? Thanks for the info.

[nogrey]

If you end up tearing them down, use an ultrasonic cleaning machine to get crud out of all of the nooks and crannies. As far as a chemical goes, I use Krud Kutter Parts Cleaner. Heard many others work too, but this is the one that gets rid of those nasty green deposits.

Krud Kutter. I'll look into getting some of that. I don't have an ultrasonic cleaner. I've sure wanted one though. Do you have a suggestion of one? Gotta watch the bank account. Wife thinks there's a hole in it somewhere, and it has my name on it. 

[jim@98valkyrie.com]

If you end up tearing them down, use an ultrasonic cleaning machine to get crud out of all of the nooks and crannies. As far as a chemical goes, I use Krud Kutter Parts Cleaner. Heard many others work too, but this is the one that gets rid of those nasty green deposits.

Krud Kutter. I'll look into getting some of that. I don't have an ultrasonic cleaner. I've sure wanted one though. Do you have a suggestion of one? Gotta watch the bank account. Wife thinks there's a hole in it somewhere, and it has my name on it. 

I bought an ultrasonic cleaner very similar to this one. Jut make sure the tank measurements allow for immersion of at least one carb. I have skipped the basket to get a bit more room.


https://www.amazon.com/VEVOR-Commercial-Ultrasonic-Capacity-Solution/dp/B01HGNM5WE/ref=sr_1_10?ie=UTF8&qid=1490973667&sr=8-10&keywords=ultrasonic+cleaner

Only place I've found that stocks the Krud Kutter is Tractor Supply. I think there is one in Kuna....

[98valk]

not all '97s have different cams.  I've found 49 state '97s with emission cams.

38s and larger main jets are too rich unless after market exhaust (larger head pipes) and air box mods.

there will be a better snappier throttle and response with stock 35s with mixture screws opened up to 2 to 3 turns open.

only run regular gas.
as mentioned run a few cans of B12.  then always run fuel valve cleaners with the new PEA formulation of cleaners.

Really good info here. I still have the old 35's that came out. Probably should get a new set. I'll get a few cans of B12. I have been running only non-ethanal regular, 87 octane through her unless I'm on a road trip and can't get it.  Any way I can find out what cam mine has in it? She was number 886 off the assembly line in '96. I'll have to look into the PEA formula thing. I don't really know that much about additives. I'm guessing they would be present in top tier fuels? Thanks for the info.

just pull valve covers and u can see if an R1 or R2 is on the one end of the cam's shaft. R1=HP R2=emissions. see here
http://www.valkyrieforum.com/bbs/index.php/topic,54105.0.html
http://www.valkyrieforum.com/bbs/index.php/topic,80073.0.html

Top Tier and PEA both are suppose to meet the cleanliness requirements for the back of the valves. High temp detergents which won't solidify on the back of the hot valves. That's why I don't like seafoam and marvel mystery oil, low temp solvents that solidify. Seafoam has pale oil which doesn't ignite easily, less than diesel fuel, too much could be cause of Hydro-Lock.
Gumouts top product list PEA on front label. Maybe more concentrated than Top Tier.

[nogrey]

Thanks for the great info. This forum is the best!