Slow Speed Jets and Bowl Screws

[Marty_in_MN]

Hello:

I have a 2000 I/S with around 12K miles on it that has the common problem of stumbling off idle, but then runs fine beyond a 1/16 or so turn of the throttle. From the research that I've done, it looks l need to work on the slow speed jets. I have opted to remove the carbs from the bike to do so since I've read about some issues of accessibility, stripped bowl screw heads, or the jets with seized/frozen threads. I have also decided to replace the jets outright, and replace the standard bowl screws with the hex socket head type and flat washers under them. Looking for some help with following...

- I've found that Chapparal sells slow speed jets for a good price of under four dollars. They have a Series 21 line of them, and they look like the right ones (I'm guessing that part number 21-35 is for a #35 jet), but I'm not sure. Can anyone help me with this?

- Does anyone know what the size and length (with flat washers under the heads) of the hex socket head cap screw for the screws that hold the float bowls on?

- What are some tips for removing and installing the carbs?


I'm also planning on doing a complete tuneup: valve check/adjust, plugs, air cleaner, carb synch (with a Carbtune tool), and would welcome opinions and assistance with those tasks too.

Thanks in advance,
Marty

[John U.]

 Hey marty,m any of us have replaced the 35 slow jets with 38s to reduce clogging. The Chapparal 21-35 is the right number for stock jets 21-38 for the larger ones. You will need to adjust the pilot screws to 1 1/2 to 1 3/4 from lightly seated if you change to 38s. Sudco has them also #KE019-006 for the 38s http://sudco.com/
Replacing the bowl screws is a good idea. I bought mine at a local hardware store by matching one of the  oem philips.
I didn't remove the carb bank. If you remove the tank and airbox you can tie the carb bank up, one side at a time. Access is tight for sure. A right angle ratchet with a JIS phillips bit and an inspection mirror worked for me.
You might want to consider desmogging while you have things that far apart. There is a write up on it in the Shop Talk section.
Good luck

[john]

pardon me...
you have a nine year old valkyrie interstate with 12,000 on it ?   
sounds like it needs a road trip ... 
ride the motorcycle  ... put some miles on it

[ptgb]

pardon me...
you have a nine year old valkyrie interstate with 12,000 on it ?   
sounds like it needs a road trip ... 
ride the motorcycle  ... put some miles on it

This will really throw you then... in September, I bought a '99 I/S with 5,000 mi. Won't have that few for long though..........

It stumbled pretty bad too.... Seafoam took care of it.

[longrider]

There are a few low mileage valks around.  Like the post above I bought a 99 tourer last May with 5500 m on the clock.  She doesn't idle like she should so I'll be changing jets next month after Mother nature moves about 3 feet of snow.  Temp here right now is -4 f.  When will it ever end!

warren

[sandy]

Do the simple things first. Use Seafoam or Techron in the fuel for a few tankfuls. If no cure; adjust the pilot screws to 2 - 2 1/2 turns out from being lightly seated. Have a shop synch the carbs and I'll bet you'll be happy.

[9Ball]

Hello:

I have a 2000 I/S with around 12K miles on it that has the common problem of stumbling off idle, but then runs fine beyond a 1/16 or so turn of the throttle. From the research that I've done, it looks l need to work on the slow speed jets. I have opted to remove the carbs from the bike to do so since I've read about some issues of accessibility, stripped bowl screw heads, or the jets with seized/frozen threads. I have also decided to replace the jets outright, and replace the standard bowl screws with the hex socket head type and flat washers under them. Looking for some help with following...

- I've found that Chapparal sells slow speed jets for a good price of under four dollars. They have a Series 21 line of them, and they look like the right ones (I'm guessing that part number 21-35 is for a #35 jet), but I'm not sure. Can anyone help me with this?

- Does anyone know what the size and length (with flat washers under the heads) of the hex socket head cap screw for the screws that hold the float bowls on?

- What are some tips for removing and installing the carbs?


I'm also planning on doing a complete tuneup: valve check/adjust, plugs, air cleaner, carb synch (with a Carbtune tool), and would welcome opinions and assistance with those tasks too.

Thanks in advance,
Marty

Sounds like a good plan.  You'll be happy with the results.

Here's a tip....if you go to HDL parts fiche and find the screw you're looking for, the description gives the size.  In this case, the bowl screws are 5mm x 16 mm (part #26 on the schematic)

http://www.hdlparts.com/fiche_section_detail.asp?section=148147&category=Motorcycles&make=Honda&year=1999&fveh=3467

The Seafoam thing is only a band-aid once the jets are gummed up....YMMV

[Marty_in_MN]

Hi Everyone:

Firstly, thanks for all the replies to my questions. I'm going to order the jets either tonight or tomorrow, and follow up with the screws and washers too.

What are the size(s) of the Motion Pro tools that one uses to take out the slow speed jets and/or adjust the air screws with? I noticed that they come in a few different diameters.

Marty

[woefman]

pardon me...
you have a nine year old valkyrie interstate with 12,000 on it ?   
sounds like it needs a road trip ... 
ride the motorcycle  ... put some miles on it

Sorry for editing my post, I tried to do this on a ipod...what a nightmare...how does anyone type on those things, I will never know......

I have a Valk ct tourer. I only have 9000 on clock
 Some of us have multiple bikes.  I ride a goldwing GL1800 as well
Just started riding the Valk steady for last few weeks because of the fear I might clog up the jets.

[bikerboy1951]

I ordered  slow and main jets from Chaparral.  Of the twelve jets ordered, two slows and one main were actual Keihin jets.  I checked the others and they varied from the stock Keihins.  At least make sure that all the jets you receive are the same.  Otherwise it could bew a real bear trying to sync the carbs.

Brad

[Ricky-D]

You should always consider the elevation where you normally ride.

At higher elevations the fuel/air mixture tends to become more rich due to the less dense atmosphere.

So if you're having problems now, you will only exacerbate the problem by going to larger jets.

***

[BIG--T]

The more I read about carbs and my Bro-in- Law paying about $900.00 for his, I'm really getting paronoid! I know to put Seafoam or Stabil during the winter months. I would assume contantly putting in cleaners couldn't be good for the seals and diaphrams.

So having said that I don't plan to put any treatment in it during riding season unless I feel I need to. Please correct me if I'm wrong.

Thanks

[fordmano]

5 years ago when I bought my 1999 I/S (with only 232 miles on the odometer) I ended up letting the local stealer have at it, it still had a few years left on warranty and i figured that might help safeguard my cost if they found anything out of whack.

Well I spent right about $1,100 for carb rebuild and sync coolant flush, oil change and service checkup (whatever that was)

*********************************************************
A post from another thread about carbs stuff posted yesterday.

I went with Rocky Mountain ATV ( www.rockymountainatv.com ) and they had the best prices, shipping was fast although if I remember correctly one of them was NOT Keihin parts but a no name type. But all of each set were of the same manufacturer. I think I gave $44.xx total cost to my door.

[JC]

If you are pulling the carbs to do this (which I recommend), then go ahead and do a complete rebuild. I found the 14 year old o-rings and gaskets were as much of the problem as were the jets on my 97 Tourer. Do  a good carb sync when you're done and it'll run like a new bike. Redeye Tech has all the o-rings and gaskets at a reasonable price, http://motors.shop.ebay.com/redeye.tech/m.html?_nkw=&_armrs=1&_from=&_ipg=

and +1 on the desmog!

[BIG--T]

Thanks for the education. I try to a least ride mine a couple days a week or 200 miles or so on the weekends. Maybe I'll get lucky. Just curious, the manual call for 87 octane and is hard to find gas w/o ethyenol. Would a higher octane help?

[John U.]

XGUY, I've had partially clogged slow jets after only 5 days of no riding. I guess the quality of the gas and humidity have a lot to do with it.
As a result, unless I'm on a trip or palnning to ride soon, I treat each tank with a low dose of Marine Stabil, which is green and a much better product than standard Stabil (was, I haven't used it in so long I don't know how it is now). You never know when other plans or a period of rain could result in a long period of no riding.
Another opinion added to the blend. 

[BIG--T]

XGUY, I've had partially clogged slow jets after only 5 days of no riding. I guess the quality of the gas and humidity have a lot to do with it.
As a result, unless I'm on a trip or palnning to ride soon, I treat each tank with a low dose of Marine Stabil, which is green and a much better product than standard Stabil (was, I haven't used it in so long I don't know how it is now). You never know when other plans or a period of rain could result in a long period of no riding.
Another opinion added to the blend. 

Thanks for the heads up. I'll try the marine stabil- couldn't hurt!

[schuitzz]

XGuy made a comment that no one really replied to and it is one I am really wondering about.  I have a 98 Tourer with 65k on it.  A few years ago it developed a low end miss.  If I'm not careful I can look like a newbie by stalling at an intersection by not giving it some extra gas.  I had the carbs cleaned, synched, did a desmog, and last year had a full dealer tune up.  It ran great for about three weeks and then back to the miss.  I tried Seafoam and nothing.  Then magic!  I tried Techron and it ran great.  Second tank after the Techron, ok and then back to the miss.  Every time I add Techron it runs great.  Can I run Techron all the time (my gut tells me no), but it sure runs better with it.  If not, any ideas as to what's causing it?  Thanks.

[BIG--T]

XGuy made a comment that no one really replied to and it is one I am really wondering about.  I have a 98 Tourer with 65k on it.  A few years ago it developed a low end miss.  If I'm not careful I can look like a newbie by stalling at an intersection by not giving it some extra gas.  I had the carbs cleaned, synched, did a desmog, and last year had a full dealer tune up.  It ran great for about three weeks and then back to the miss.  I tried Seafoam and nothing.  Then magic!  I tried Techron and it ran great.  Second tank after the Techron, ok and then back to the miss.  Every time I add Techron it runs great.  Can I run Techron all the time (my gut tells me no), but it sure runs better with it.  If not, any ideas as to what's causing it?  Thanks.

Thanks for bringing that up since no one answered, but am sure someone will. I don't claim to be a mechanic but know that a cleaner can't be used constantly, especially Techron which IMHO I think is the best cleaner. I am just trying to put good gas and ride it at least a couple of times during the week and every weekend, weather permitting. At the first sign of running rough and knowing it's not electrical, I'm putting Techron in for a couple tanks. 

[John U.]

I have an I/S like that. It clogs quicker than it should. I really think I have a partial clog with piece or two of rust. Anyway, whenever it gets running rough I put a low dose of Techron in a full tank and it clears up, by and by.
The only time you need massive doses is when the bike barely runs without the choke.
I've been doing that for years with no ill effects. Whenever I find Techron on sale (as it is now at Autozone- buy one, get one free) I buy some so it's always on hand.

Pulling the carbs to clean them may provide that warm "I've accomplished something" feeling but I'm warm enough, even in the winter. 

[BIG--T]

I have an I/S like that. It clogs quicker than it should. I really think I have a partial clog with piece or two of rust. Anyway, whenever it gets running rough I put a low dose of Techron in a full tank and it clears up, by and by.
The only time you need massive doses is when the bike barely runs without the choke.
I've been doing that for years with no ill effects. Whenever I find Techron on sale (as it is now at Autozone- buy one, get one free) I buy some so it's always on hand.

Pulling the carbs to clean them may provide that warm "I've accomplished something" feeling but I'm warm enough, even in the winter. 

Yeah, mine would really have to be running on 3 cyls. to pull the carbs in this 85* weather we're having! Lol  Glad you told me about the sale. I buy the bottle that treats 12 gals. and put 1/2 to a tank.