How and Why You Need to Rebuild the Vacuum Petcock on Your Motorcycle

Step by step process on how to rebuild almost any style of motorcycle vacuum type petcock.
A close look at typical internal parts that may fail and how they may negatively impact your motorcycle engine . Another key element to remember about vacuum petcocks is that the prime setting is used to bypass the vacuum feature .Its is not meant to be left in that position .The prime setting is typically used only to fill empty carburetors if you run out of fuel. Once the bike has started remember to reset the petcock into the on setting . Unlike what I did at the beginning of this video .
To learn some very interesting facts and tips about your motorcycle chain ,that many people do not know ,but should .Click the the link below ,you'll be glad you did .
• Motorcycle Chain Facts...

[@TRyanLearnBikes]

To learn how to fix the number one most common issue of carbureted motorcycles click the link below .You will be glad you did. kzbin.info/www/bejne/pnbFaZysm8aUps0

[@juhaposo5742]

Leaking petcock and needle valves are the problems what I have found also in my veteran 125cc 2-stroke bikes. It's really irritating to find petrol everywhere it shouldn't be. As a matter of fact I renewed petcock's seals of 2-3 bikes I own, but the problem continued, until I realized the petcock spring needed re-organizing/stiffening. Watching videos like this from Ryan pays - it makes You better understand what lies behind the problems and You are not alone with these irritating problems getting Your bike again on the road. Getting new petrol valves from EBay is frusthrating because some of them aren't sold anymore, anywhere, for example: Yamaha RD 125 1974 Teihin carbs. I have thought by now that it would be better for me instead trying to find any new ones, but instead try to find and buy a pair of matching Keihin carbs instead. In Europe (I actually have a new repair kit to them) Keihin carbs repair kits are much easily available. Though, I'm still interested if someone have these and is willing to sell buy those new Teihin petrol valve needles. Thank's for the video, I found it most interesting!

[@TRyanLearnBikes]

@juhaposo5742 You raise many interesting points .The fact you're experienced at working on older two strokes and have been able to diagnose problems accurately is worth it weight in gold .We have an uphill battle finding quality parts these days for sure. Especially as OEM bits aren't easily acquired from dealers either. So it leaves us improvising. Thanks for watching and for taking the time to leave such a great comment. Cheers to you good sir 🍺

[@alainmaurice5383]

I just followed your tutorial to renovate my petcock on my DR650 - 2002. It will help me a lot. The little details you show make all the difference. Thank you very much Alain

[@TRyanLearnBikes]

@alainmaurice5383 Hi Alain.Im glad the video was of some value to you .I really appreciate you taking the time to comment and let me know .Ride safe out there. Cheers 🍻

[@SpyderWayne]

Even though I haven't seen or used a petcock in the last few years, I knew I'd enjoy this video. Your wit continues to shine, and the cocky humour with your pet rooster... priceless 😳😁🤣👍

[@TRyanLearnBikes]

Ha ha Thanks Wayne. Well crafted comment I genuinely appreciate your creative bants. Thanks again for watching and taking the time to comment so kindly as always. Cheers my friend 🍺

[@AlexPtc89]

Have one vacuum operated on my xj600s

[@justinb5304]

Thanks bud! My tail pipe is pouring out , after being blown away from learning about how silly its issues were. Lol Braap braap

[@TRyanLearnBikes]

Thanks for watching and taking the time to comment so eloquently. Cheers

[@rickc2222]

How do you only have 6.5k subscribers? your video content and quality is among the best....

[@TRyanLearnBikes]

Hey man thanks very much for such a kind comment .It was great to wake up to first thing in the morning .Cheers 🍺

[@rolandkeith5322]

I made comment about the Marantz Tuner Amp in view of this clip. And nice quality work here as always, by the way and a very helpful How too! video. I collect vintage Hi Fi and a have a fair collection at hand.

[@TRyanLearnBikes]

Hey R.K. Nice catch seeing the old amp strategically placed in view for those in the know to spot .I kind of figured you might key in on it as you are a radio tech man . The marantz is a solid bit of kit ,still works great .Bought it new many years ago ,still have the original paperwork .It's been all around Canada with every move I made . I even have a small transistor radio my dad gave me for my 7th birthday .Original box and paperwork and still works ,a little crackley but still pulls a station in . There's even a few old tube radios on the shelf that still work from back in my childhood . I bet you have a bunch of cool radios in your collection too.

[@rolandkeith5322]

That’s very cool you have your old transistor radio from when you were seven and if you run it every now and then for a few hours at a time that will keep it happy. What model is that Marantz tuner amp? …… You have some Tube radios man how cool, send me some photos through email of them when you get a chance I would love to see them. I do have some tube radios around the house in the kitchen in the mornings I catch the news on a 1953 tube portable that has mains power as well and another tube radio in my entry that gets a run on the weekends and another in my lounge room that gets a run once a week as well plus a whole heap of hi if and tube radios in a storage unit plus other things. One thing with the tube stuff is it is non effected by any EMP’s that might hit the world at any time from whatever. One day I might do a video on my collection of Hi-Fi as that stuff does well on youtube but in some ways I have an embarrassing quantity of stuff stored so I don’t know about making a vid on it all. Like just in amps of many different brands I have 3X 8 foot stacks of them all good brands and quality items through to a few different full sets of even bang & Olufsen systems. Real to real tape recorders form studio through to home Hi-Fi ones, Hi Fi EQ’s, tuners turntables tape decks oh man you name it….like I said it’s an embarrassing quantity of stuff. I plan to sell off much of it though and just keep a few very high end sets of systems as these days it all just sits in storage doing nothing so someone may as well enjoy it. Up-stairs hooked into the editing computers and the X box I’m running one of Sony high end amplifiers from the mid 70’s with a very cool high end digital sound processor plumbed up to it, all connected to some rather expensive speaker system that totally kicks butt. And that gets used daily. I got some very cool Marantz components and amps all around the mid to late 70’s but much beyond that when they started making them in Japan I stopped collecting them as they went down hill from there. Your amp is very serviceable though so if it stops just get it fixed as the value of these things is getting up there now days and you can’t replace the quality unless you go very high end. @@TRyanLearnBikes

[@TRyanLearnBikes]

@@rolandkeith5322 Holy moly man you're into it big time .I sent you a few pix via email. Have a look when you get a chance. Cheers 🍻

[@rolandkeith5322]

shall do i just got up and having a coffee so when I get into my office I will check them out and thanks for sending them @@TRyanLearnBikes

[@louisdegroelard2028]

You are An amazing KZbinr. Love your style and fluidity. Thank you very much for your nice videos!

[@TRyanLearnBikes]

@louisdegroelard2028 Well thank you very much .This is one of the nicest comments I've received in a long time .I really appreciate you taking the time to do that ,Cheers 🍻

[@louisdegroelard2028]

@@TRyanLearnBikes You're welcome :) I'm certain I will keep on learning a lot from your video's! Wish you the best

[@TRyanLearnBikes]

@@louisdegroelard2028 Thanks very kindly..I genuinely appreciate you watching and for taking the time to comment..Cheers

[@FerRrocha]

A side from having super usefull information, the way is all explained is amazing. Big fan of the video. It should have way more likes !

[@TRyanLearnBikes]

@FerRrocha Thank you very much. I truly appreciate your kind comments .It's great to hear that you got some useful information out of it .I also appreciate the fact that you took the time to let me know .Cheers to you good sir 👍

[@FerRrocha]

@@TRyanLearnBikes I GRINDS my gears (no pun intended ) when videos give me 80sec of intro followed by 90sec of personal life story and 10sec of actual info and ends with 100sec of shout outs . I wish to give awars to videso like yours . Years a go I stumbled into a video for a shadow 600 talking about how to rewire the kick star sensor. " HI Cut this wire Cut this other wire and tape the ends . THE END" AMAZING video . lol

[@TRyanLearnBikes]

@FerRrocha I agree 100% . The long intro with heaps of irrelevant information is useless and such a waste of time .Short and to the point is definitely the way to go. I appreciate you mentioning this point .I hope other people read your comment. Thank you very much ...again..cheers to you good sir 👍

[@williamstarkes9302]

You really know your petcocks. Nice tribute to Sydney.

[@TRyanLearnBikes]

Thanks very much young William .Not many will catch the Syd angle .Well done . I'm guessing you didn't see the ballerina though ,did you?

[@RonHei]

Love your videos! They’re funny, knowledgeable, interesting, useful, entertaining and awesome. Thanks! Oh, the video editing is killer.

[@TRyanLearnBikes]

Hi Ron .I have to thank you for making my day with your kind comment .I truely appreciate that you like some of my videos and that you took the time to leave a great comment like this one. Thanks very much .Cheers to you good sir

[@Trikekid84]

Great video! Your intake and exhaust valves must have booth been open for the gas to fill up the exhaust.

[@TRyanLearnBikes]

Hey thanks man I appreciate that . Ya the whole concept of fuel getting into the engine like that raises some serious questions for sure . It seems almost impossible on a four stroke but a two stroke does pose a different situation . Case in point ,the little 350 in the video is a two stroke . Thanks for watching and for taking the time to comment .Cheers

[@adamhorner7679]

Vary helpful it's surprising how meny videos u can watch without anyone fully explaining

[@TRyanLearnBikes]

Thanks very much, Adam .Cheers to you good sir 🍺

[@GoldenBoyGarage]

Video editing is top notch!

[@TRyanLearnBikes]

@GoldenBoyGarage Thank you very kindly for taking the time to watch and leave such a great comment. Cheers 🍻

[@PurpleMonkeyWaffle]

Nice rebuild Ryan. Its great to be able to keep these bikes alive thanks to rebuild kits continuing to be made. If only the manufactures still made the parts we ACTUALLY need lol. Like stators and flywheels!@!@

[@TRyanLearnBikes]

Thanks very much .And yes it seems the parts we really need to rebuild or buy new are just getting harder and harder to find .I guess thats what makes our vintage bikes increase in value as time goes on .Kind of a double edged sword .

[@fcdevreugd9449]

So I'm also that idiot that left it on PRI for 8 months. Bike doesn't want to start at all. Also thinking about checking the petcock vacuum. How did you get it to run after?

[@TRyanLearnBikes]

You're not alone its a common thing to have happen . If your bike is a two stroke the space below the piston could be full up with fuel and could definatly cause starting problems and potentially catastrophic if it somehow did .And because there is no drain plug that can be a chore to empty it . If its a four stroke unless you've checked the gearbox for fuel contamination that could be full to the brim with fuel and oil too and could make the bike hard to start for sure . If neither condition applys start with the basics ,Check for spark , check for fuel flow , check for air flow . That should do it . Curious ,,,what make model and year of bike are you dealing with

[@MrShrimpy72]

You should have more followers. Great stuff.

[@TRyanLearnBikes]

Well thank you very much MrShrimpy72 (great name by the way ). Thats very kind of you to say .But as you know this youtube game is a tough landscape to navigate sometimes. If our only motivation was followers it would be hard to continue creating .I rarely look at analytics.Its not why I'm here .Thanks for taking the time to comment so kindly .Cheers my friend

[@MrShrimpy72]

Ha! Great way to look at it. And a thank you for your fork rebuild video. As a result I rebuilt the forks on my boys YZ and they are working like a charm.

[@TRyanLearnBikes]

@MrShrimpy72 My pleasure,it's great to hear you were able to spruce up your young lads YZ forks with some help from one of my videos .Thats what its all about .Thanks for letting me know .Cheers again my friend

[@MD-rz2ht]

Thanks for the great video!

[@TRyanLearnBikes]

My pleasure. Thank you for the great comment. I genuinely appreciate it. Cheers 🍻

[@xzouix]

Good info! I rebuilt my yamaha xv535 with a rebuild kit (fewer parts - only the rubber ones - the kit didn't come with the metal parts that you call "essential", so i only replaced the rubber parts (btw. my petcock has only "on" and "off", no prime option, and the reserve button is on handlebars). Anyways, I rebuilt the petcock because it was leaking. I swear i did everything right, all the parts went to the right place, the petcock doesn't leak anymore. However, the bike now keeps shutting off, and only runs when i switch to "reserve" . Can you give me any suggestion what could be wrong? Thank you!

[@xzouix]

(one thing I don't remember (because I did the rebuild in summer) is whether I checked the alignment on the breather hole on the diaphragm and the hole on the petcock itself. Could that be the reason for the bike only running on reserve? I am wondering, if not that, what else could it be?)

[@TRyanLearnBikes]

@@xzouix Well thats an interesting one for sure . I took a quick look at the parts list on that particular petcock .There is a rubber gasket with a very particular set of holes .Its part number 3AJ-24523-00-00 If you type that into the google search bar you'll see it . If that was somehow put in upside down I'm thinking it could mess up the standard flow of the petcock .Does that look familiar to anything you may have had as part of the rebuild kit ?

[@xzouix]

@@TRyanLearnBikes now I remember, it was Tourmax fuel valve repair kit for XV535, and yes I did align everything including the diaphragm holes. It is not the OEM kit, but all parts fit perfectly to the spec, I compared them with the OEM parts. I also tried to blow through the petcock with the position switched to "on" after I rebuilt the petcock just to make sure I didn't mess the on and off position. Besides the petcock I did all fuel lines on the bike (new hoses, fuel filter and all). I have the motorcycle manual, so i am pretty sure I didnt leave out any steps.

[@TRyanLearnBikes]

@xzouix hmmm...jeeez man this is a good one ...now I'm really curious as to how this could be . I'll be at the shop on Tuesday and talk it over with two of the best mechanics in the game.Im sure they will have some interesting theories as to what could be going on .I will update you then .But in the mean time if you figure it out please let me know .I'm very interested to see what this problem actually is .

[@xzouix]

@@TRyanLearnBikes Thank you. If I figure it out, I will respond to this thread.

[@maxwell9734]

🐓 Nice Bird! 😅 Great job on the video, too. Hey, I noticed that whitetail Buck's rack, above the parts washer... what's the story on that? 🦌

[@TRyanLearnBikes]

Thanks very much. Nice catch on the rack , not many would notice that one .There's not much showing but it's moose antlers a friend of mine nailed in Northern Ontario. And the rooster is my buddy Tim's. It's a great bird , very very chill. Thanks again for watching and commenting. Cheers 🍻

[@maxwell9734]

@@TRyanLearnBikes oh, No Wonder it looked so HUGE! 😂

[@rolandkeith5322]

What! you have a tube tester as well.....?

[@TRyanLearnBikes]

Well yes I do, I'm curious how you know that .I watched this video over a few times to see if it was in the background somewhere and came up empty handed .So I have to ask R.K. how did you know ? Is it in some other video ?

[@rolandkeith5322]

@@TRyanLearnBikes In the The Kane and Sage Magic Show video buddy

[@TRyanLearnBikes]

@rolandkeith5322 Ahh yes ok ..I forgot about that channel..Man Oh man ..R.K. you have a great eye for detail .To be able to spot and identify that tester in such a short period of time is quite impressive .You certainly know your stuff in the electronics world. Wow .

[@rolandkeith5322]

@@TRyanLearnBikes I do you reckon? well you must do to have one of those as I don't. I have to go for a 50 minutes drive way up in the hills to see an old mate of mine that builds high end Hi-Fi amps and repairs all old tube stuff to get mine tested.

[@TheGameboy57]

i would think that one person's theory of the wind pressure on the exhaust pulling fuel from the carb/tank wouldnt work because the intake and exhaust valve shouldnt be open at the same time, but you did manage to dump fuel into the exhaust by just leaving the fuel petcock on, so i dont know lol

[@TRyanLearnBikes]

Yes I did run that idea as well and a few other buddies had mentioned it doesn't stand up to scrutiny. So I don't know man .When I talk to guys at the track about it I'm getting about a 75 /25 split in favor of "it wouldn't happen "..but the ones who say it could and does happen are steadfast in their position. Maybe I need to do a deep dive and get the real answer that 100%.Thanks for the idea ..it could make a great video .Cheers

[@aleksandarnedeljkovic3659]

Hi I am riding Honda Hornet CBF 600 year 2001 and I did fix carburators and my fuel tank. Nevertheless, when I am riding after 50-100km (somethimes much earlier) my bike just shuths down, firstly it loses its power. Could it be failuer of fuel valve, bike does not receive fuel?

[@TRyanLearnBikes]

@aleksandarnedeljkovic3659 Hmmm ..ok thats an interesting problem for sure .How do you get the bike started again .Do you have to wait a specific amount of time or does it start right back up ?

[@aleksandarnedeljkovic3659]

@@TRyanLearnBikes Hi, thank you for answering , I started to lose hope. It will not start immediately I do not know how much time it needs exactly but last time I let it through night. In the morning it starts normaly and i ride it for couple kilometers. Bike has power everything acts normaly and the same thing happened lose power and stops. After 10-15 minutes I started it again and ride back home (couple kilometers back). Could this valve stops flue flow ?

[@aleksandarnedeljkovic3659]

​@@TRyanLearnBikes Hi , thank you for answering , I started to lose hope :) I started it normaly on ignition button but it wont start immediately, I have tried. I do not know how much time it needs exactly.Last time I let it through night. In the morning I started it normaly on ignition button, runs great for couple kilometers has power, great on gas and then it happens again , lose power and stops .In order to come back home I let it for 10-15 minutes then started on ignition button and I ride it normaly back home (couple kilometers back). In front of my house it stops again, same thing. Could it be flue valve ?

[@TRyanLearnBikes]

@aleksandarnedeljkovic3659 OK...I don't think it's a fuel tap issue , but you may be able to prove it by running the bike on the prime setting. That should take the vacuum requirement out of the picture . If the bike still shuts down using the prime setting you can assume the fuel tap is not the problem. When you get a chance let me know if that works .Then we can look deeper .

[@aleksandarnedeljkovic3659]

Well I do not have prime option. My valve has on, off and res(reserve) options.

[@SolorideryR6CX650C]

Is it a bad idea to run the bike on reserve only??? Mine works only on reserve. That’s not a bad thing is it????

[@TRyanLearnBikes]

@SolorideryR6CX650C Hey Rider, no, it's not a bad thing to run on reserve all of the time other than the risk of maybe running out of fuel without a backup option. It may be worth checking out why it only works on reserve. It might be an easy fix once you get inside and have a look .But until then, just keep riding and have fun .Cheers buddy 🍻

[@Concretefarm]

Hey bud i would like one of those any monkey can take it apart t shirt lol 😂

[@TRyanLearnBikes]

Ha ha .. Those were a limited run from the team at Ultimate Cycle in Hamilton. I'll ask if there are any extras kicking around , maybe you'll get lucky.

[@rolandkeith5322]

hey buddy I did drop a comment here a few hours ago but it's gone? AI doing it's thing or what?

[@TRyanLearnBikes]

Hi R.K. .There are only two comments visible to me at this time .This comment thread here that I'm responding to and another one where the first sentence is you mentioning about the Marantz tuner in view .I'm not sure what happened to any other comments .I didn't flag or restrict any comments .I guess A.I. can step in any police comments as it sees fit .It happened to me one time when I tried to make what I thought was a funny comment and it actually responded back to me with a warning and a link to review acceptable comment policies .Holy Moly what a soft marshmallow world we live in these days man .Do you think your missing comment could have crossed the marshmallow line in the sand in the eyes of KZbin A.I ?

[@rolandkeith5322]

Who knows man but I put the comment up and it was there then a while later it was gone, but this has happened a few times now on comments and I have had others say the same to me as their comments have gone missing. Eh! The internet gods are not kind to us anymore I think as odd stuff happens often. Never mind I topped you up on the latest comment I just did now so all should be good I hope. @@TRyanLearnBikes

[@pmfilmsUK]

Fantastic

[@TRyanLearnBikes]

Thank you very much Patrick , I appreciate your kind comment.Cheers🍺

[@antoniomodesto1157]

I replaced the petcock on my XV250 with a manual one. Rebuild kits here in Brazil are crap

[@TRyanLearnBikes]

@antoniomodesto1157 Thats a good idea .I prefer the simplicity of a manual fuel tap too.

[@Jarvisbiker]

Paging Dr, Ryan !!!

[@rolandkeith5322]

Hey buddy I have not got to the email you sent as yet and it is not from trying either but my email program for some odd reason has locked me out form using it so I am waiting for a tech guy to come and sort it out as it's my office computer. I only have email on just the one computer. I think some kind of update went through on some other systems on that system for work but it some how has locked me totally out and it's a pain in the butt. And given it is so close to Christmas the tech guy is flat out too so with luck it will be fixed tomorrow.

[@TRyanLearnBikes]

Hey R.K. .Yikes that doesn't sound very good at all .Hopefully you get that resolved soon .It would be quite frustrating to be locked out of email contact for sure. Once you are back up and running let me know if you got the email I sent .Cheers for now Buddy .

[@rolandkeith5322]

yeah I will man, with luck it will be some time today it gets sorted. it's a bugger as a quite a percentage of my clients bookings come through email even though the email account is split personal under one address and work under the other if you get me.@@TRyanLearnBikes

[@3209-f4h]

9/1/24 I got a vac. One from amazon for $17 new!

[@TRyanLearnBikes]

Good stuff.👍

[@3209-f4h]

No, on the traveling venturi… bc there’s a intake or exhaust valve closed / cylinder! Wouldn’t even happen on a 2 cycle with reed valves! NO,

[@TRyanLearnBikes]

Ya I was kind of thinking that myself but then someone mentioned rotary valves on a two stroke ,so I don't know .What do think about that scinerio ?

[@choppergirl]

This piece of absolute Honda Shadow safety grrbage will leave you stuck at home, stranded away from home, or worse, have you tearing your bike apart trying to figure out why your bike isn't cranking. My vacuum pump does not have a Prime setting, it has ON, off, and REServe. Everything is groovy until your carb bowl is empty. It's not cranking because your fuel line is bone dry even though you have the petcock on and the fuel tank full and no matter how much you turn it over it's not creating enough vacuum to activate it. I want this P.O.S. OFF MY BIKE. Someone recommend some old skool aftermarket part that fits and can screw direct into the tank that is just a traditional petcock. Where that metal tab is at 9:00, I have an open pipe venting to atmosphere. Maybe there is a tab on the other side, that is getting stuck like your rare case scenario, maybe there is not, I don't care. If you cover this vacuum leak exit with your finger and turn the bike over, it will allow gas through. If it's uncovered, sometimes it will, sometimes it won't (like mostly in the morning when it's cold). If my petcock is in the ON or RES position, it better gd be flowing fuel, no questions asked, no monkey business, no non-sense safety part that can break and halt all fuel going to my motorcycle leaving me turning over the motorcycle until the battery is dead. This is a case of design where newer was not better, but was way worse.

[@TRyanLearnBikes]

Well....you make some very interesting points. Thanks for taking the time to comment and share your experience on the subject. Cheers 🍻

[@choppergirl]

@@TRyanLearnBikesThe more I dug, the more I found... Honda had a recall RCRIT-08V141-7306 on that vacuum petcock for my 2008 Honda Shadow 750C2 !@#$%. I don't know if it's the recall for it failing, or the fact it's 16 years old... if it hasn't been replaced before :-/ Either way, it's getting replaced. I just rebuilt a Honda Rebel carb and my hands smell like Berryman's B12. This is working on fuel system crrp is not fun. I pray to the heavens I never have to take out a dual carb buried in something. I'm just going to keep running solvent through them every tank up.

[@TRyanLearnBikes]

@@choppergirl Agreed ,working on the fuel system on most any bike can be a chore for sure .I had to look up what Berrymans B12 was . Thanks for the tip ,it sounds like something I should be using occasionally .Hopefully you get your bike sorted out soon and you can get back out riding .Thanks for taking the time to comment and inform .Ride safe .Cheers

[@edinpandzic5838]

does my motorcycle even have this lol...never seen it

[@TRyanLearnBikes]

@edinpandzic5838 I'm not sure ...what year make and model is your motorcycle?

[@edinpandzic5838]

@@TRyanLearnBikes its honda nc750x....I will look around too

[@TRyanLearnBikes]

@edinpandzic5838 There should be a fuel tap near the lowest part of your tank .If it has a prime setting then you likely have a vacuum style petcock

[@jeremybenwy5928]

Possibly not my first bike didn't. 😉