Throtte Shaft Seals a necessity to change?

I'm doing a carb rebuild, so i broke open the rack and checked the seals. they have no real signs of wear...

From what I read on these forums, everyone is always recommending to change them.


What would a worn throttle seal look like?
How snug would a new seal fit in the opening?

Need some good reasons before I order 8 pieces of rubber for almost 50 buckaroos

thanks!

 

Everyone recommends to do it because all the cool kids are doing it. More importantly chances are good the throttle shaft seals are waaayyy past due for being replaced.

Rubber, old, brittle, stiff, cracked, etc. a worn seals may look like a "normal" seal but will not perform like one. The fit will be perfect if you get them from XJ4Ever.

 

Yup, that dried out rubber is not going to seal well against the shaft. If you looked before you cleaned the carbs, you will usually see the telltale staining around the carb body where the seal is. I'll get a pic of my kaw carbs if you want to see it. Considering the amount of labor it takes to pull them off again, split up, and redo the seals I would just do them now and be done. Your time is worth something and once you put a number on it these decisions become easier. Plus you won't have to second guess anything if/when you run into an issue tuning and syncing them.

 

You don't HAVE to replace them......you COULD opt to just put things back together, and then wonder why you get lean-idle racing, hanging idles, funny surges, high lean-fuel temperatures, stains on the sides of the carbs, etc....struggle with trying to correct all that---- then finally break down and pull the rack again, and undo all the work you did before, and find out that NOW you HAVE to put new seals in. You don't HAVE to do them, but your really SHOULD do them. If you don't do them now, you WILL HAVE to do them very soon.

They can be dried, shrunken, crispy, etc......but they can also look like new, feel nice and soft. But yet they are stretched out and not sealing, or they could be nice and soft but shrunken and not sealing. I find everything from crispy to the point of having to chip them out and use solvents to dissolve the rest, all the way to ones that fall right out, to ones that are stuck to the shaft.

When I rebuild a rack, there's no alternate choice....new seals ARE going in.

 

hatachi carbs? you could use 2 orings to replace each seal #11 Buna

would you add your bike to your signiture line please.

 

^^^^+5 good chance seals are original so 30 plus years ...they are toast ...if you dunk carbs recommended method of cleaning with seals in place then seals are ruined carb cleaner is not rubber friendly.

 

Last set of carbs I did the seals looked ok but had shrunk enough that they fall out of carb bodies when shafts removed.

 

Often the case

 

Yea on mine they kinda just fell out of the opening, like when i put them back they're not visibly smaller than the opening, but not so snug that it wont fall off.

HOWEVER!
this is my first run through. So even if the bike is runny crappy, its running.

I put the originals back in for now. greased them up with a bunch of silicone though.

The next carb clean i do, i will replace them for sure.
(have a feeling i'm going to regret this)


There's so many variables though! The more I take this bike apart the more I have to do.

I removed the exhausts, and realized that there's a few rusted holes. In fact, the left muffler wasn't even attached to the exhaust, it was attached to the side of the bike, and the exhaust just kinda fit in.


I feel like I'm going down the rabbit hole lol

 

Alice, you will find many interesting and amazing things in Wonderland............

 

Hey chacal, how long would shipping usually take for your friends north of the border?

I'm contemplating pulling out the penetrating oil and busting these seals off again :s

 

I did this job Sunday afternoon on a Yamaha TX650. It was actually pretty easy on that one. Having a JIS screwdriver probably helps a lot, particularly when removing the butterfly screws.

 

Much cheaper if you have a friend across the border............

SHIPPING AND HANDLING CHARGES:

IF ORDER IS UNDER $200.00 USD PARTS TOTAL:
USA:
$ 5.95 first class mail or parcel post (7-14 days transit time)
$ 7.95 priority mail (2-5 days transit time)

Canada:
$ 11.95 first class mail (14-28 days transit time)
$ 25.95 international priority mail (7-16 days transit time)

 

I like that idea! what exact size would they be. A quick google search of #11 Buna o-rings comes vague.

thanks for your help!

If I had any knowledge to impart I would... but when it comes to stuff this, I am yet a yoot.

 

Pandora's box

 

That's why I like living 300 yards from the 49th parallel
Tee one up at end of driveway and 3 or 4 bounces it is in the US.
Most times it's less than 72 hours from email to Len and arrived at daughter in laws house.

 

#11 is the size. you can buy them at auto parts stores

 

I have a pretty big water hazard in the way! Plus an island which is neither USA or Canada. But a shipping address over there is quite useful!

 

You are a better golfer than I am

 

That's like Tin Cup, bounces very well on the road so a 250 drive goes 350

 

Regret is a harsh word... dumb. That is a better word, you will/should be calling yourself dumb.

You have just confessed and are finding out like many before you - the more things you lay hands on the more work there is to do. It is not a bad thing to have bike projects, but there WILL be quite a few of them.

It makes no sense at all to half-ass your way through the carbs and then tell yourself that you will do it better next time. You gonna half-ass your brakes? Clutch cable? You don't need all those braided wires, so what if a couple are frayed?

Annie, I love you and please don't take my potty mouth language personally. You may be really excited to get this bike on the road but patience and meticulous attention to detail will pay off big. The harsh reality is you are the best mechanic for your bike, and you need to make it as safe and reliable as possible.

Here's a little follow up story, there was this guy - he bought an XJ650, he had good mechanical skills, the bike ran well for several years. Then this guy decided to clean his carbs.... after removing and replacing them a half dozen or so times, this guy realized that although his mechanical skills were fine, and proper tools were used... he just didn't understand/ appreciate the delicate balance of all the tiny bits and pieces that are part of the carbs.

Now I ( uhhh I mean "this guy") can take his carbs in and off the bike with one hand tied behind his back and his eyes closed, which in some circles is considered high faluten - but in reality the frustration of saying "dag gum it, why didn't I do such and such the first time?" Got old really quick. Some of that such and such "that guy" didn't fully realize at the time so inexperience could be an excuse - but the whole point is IF YOU KNOW YOUR THROTTLE SHAFT SEALS ARE WORN - REPLACE THEM!!!!!!!

Just do it, all the cool kids are.

 

Darn Siri--- another typo...I think she meant:

Just do it, hogfiddles does.

 

Hogfiddles not cool kid?

 

Siri can't hear.... I think she meant:

"Just do it--- all the cool kids named hogfiddles do....."

 

Ist class mail to a bordering country 14-28 days! You guys still using mules?

 

Not at all. Just lots of red tape.

 

Mules aren't allowed to cross the border anymore

 

Didja build that wall yet?

 

Motorcycles, man. Motorcycles

 

throttle shaft seals are damn expensive... the question is are orings just as good?
should we whack felt seals in? if not?
$50 is insane for the parts and I understand that it should be done when the rack is apart but... I could wrap 8 x 5 dollar notes about the shafts and still feel ripped off.

Then again, I might just be pissed at the $25.95 USD postage to australia which makes the seals BLOODY expensive.

 

Umm. Perhaps you should speak to the guy who posted the bottle of booze. Unless that's a motorcycle related fluid.

 

Motorcycle riding preventative fluid. At least for me it is.

 

The cost of seals is cheap . If your bike runs like crap because you haven't changed them how much time have you wasted trying to tune your bike.
Anyone that I have done a total carb rebuild is happy they paid me to do it knowing that every morning that they walk out to there bike and it purrs like a kitten.

 

I am of the school of thought that motorcycles, booze, bacon etc. ok.

Religion and politics not so good.... I fear that our Friendly Hat (and the rest of the world) passes judgement based on the behavior of a few.

 

Yes, it is a picture of what NOT to put in your bike OR yourself before a ride.......

 

Thought it might be legendary "blinker fluid".
I apologise, I didn't mean for it to be political, just a joke following the "mules crossing borders" post. I don't judge one on the basis of another's actions. Some are idiots, others aren't.

 

Another view..

http://www.motorcycleproject.com/text/throttle_shaft_seals.html

 

Hmmm, interesting points about the critical nature of the shaft and potential for buggering it up.

 

And interesting to note that:

1. OUR Throttleshafts are STEEL
2. Carb dip may not ruin felts, but we DON'T have felts.
3. Our carb builders here DO have the knowledge and meticulous work necessary

 

And he's also talking about Keihin and perhaps some older Mik's that used felt seals, and, to my surprise (since I've never worked on them), BRASS throttle shafts. I'm sure there must be some advantages to using brass as a shaft material, but besides reduced machining/material costs, I can't think of any off the top of my head compared to the stainless steel shafts that the XJ/XS carbs use.

 

Yeah, a certain fox came to mind when I read that section. If that jerk saw your work, he'd retract his statement.

 

I'm pretty sure that Dave falls into the category defined in that article as a 'Dedicated Carb Rebuilder' and is rightly respected. I offered the article that I stumbled across for general interest. The guy seems knowledgeable in his field so I'm not sure how that makes him a 'jerk'. Perhaps you should ponder a while before hitting 'enter'.

 

Hi guys,

I pretty sure I have multiple problems here, but trying to narrow them down.

Installed the carbs back on the bike, and there's oil leaking really badly from the air box, coming from PCV valve. Like really, bad. There's as much oil coming out as on a Mcdonald's breakfast sandwich.
I don't want to run the engine too long because that looks like a substantial amount of oil that's coming out.

Second, the bike is idling really high. I turned the idle knob pretty much all the way out (counter clockwise). But still. The bike responds to the throttle when i pull it, but goes back to high idle.
I'm getting no readings from the odometer and rpm meter, stuck at zero, so I'm not even sure what RPM i'm running at.

Fuel levels set to 3-4mm from top of float bowl, and bench synched the carbs. Only other thing I can think of are the main jet , supposed to be 120, but these ones are 122 (from ebay..... i know). But that shouldn't even matter at idle, the butterfly valve is shut. The pilot jets are good at 43.
No black smoke coming from the exhaust (doesn't sound or look like its running rich).

I've read about an accelerator pump. Is there one on these bikes?

I'm not sure where to go from here...

 

Check the oil level first. Is it possible it filled with gas running through the carbs?
High idle probably due to air leak. At idle check with propane around the carbs, intakes and seals. If the idle increases you have found the leak.

I don’t think there is an accelerator pump on these bikes.

 

There is no accelerator pump, and no PCV valve.
The only way for oil to get into the airbox is an overfull crankcase. Either you overfilled with oil, or the float needles aren't shutting off the fuel supply to the float bowls.

I'm merging this with you other carb thread for clarity's sake.

 

Now that that's done. Did you replace the throttle shaft seals?

 

Not my style. More of a "fly off the handle" kind of guy. For evidence, see EVERY ONE OF MY POSTS! If anyone is a jerk, it's Matti.

Seriously though, thanks for the article.

 

^^^^+ MANY Your crank case is full most likely fuel ..take off fill cap take a wiff does it smell like gas? Good chance your float needles are not sealing ...did you replace them ? look at tip does it have a groove around them ...if you did not replace good chance this groove is keeping it from sealing right. As to high idle your carbs are out of synch ....even if you do a bench synch...you have to do a running synch either with a 4 gauge vacuum synch gauge ,or a mammoter set up . You also may have a vacuum leak ...what condition are your intake boots in ? And Inquiring minds want to know did you replace shaft seals ???? Did you submerge carbs in carb cleaner and replace ALL rubber seals ?