Is it worth changing over to manual petcock ?

So I’m reading these horror stories of the stock vacume operated petcocks failing and letting gas into the oil .... how many of you guys switched over and is it worth it to switch to manual ?

Here in Europe the stock petcock is manual. So lots of experience.

Personally I only switch it off in winter when I do not use the bike for longer time. Otherwise I rely on the float valve.

I thought about changing over also. But I really never had a problem on either my Dr650 or DRZ with years of use on each. I did have a problem with this issue on my snowblower while stored over the summer a few years back. Now it gets run dry. I probrably won't change them till something doese happen though.

18 minutes ago, Mariom1 said:

I thought about changing over also. But I really never had a problem on either my Dr650 or DRZ with years of use on each. I did have a problem with this issue on my snowblower while stored over the summer a few years back. Now it gets run dry. I probrably won't change them till something doese happen though.

Agreed my theory is if it isn’t broke don’t fix it , I appreciate the reply 

There are two types of vacuum petcocks on the DRZ; those that have failed and those that are gonna.

Dont believe that the Raptor petcock is the best( or is that cheapest) replacement. If you want reserve you need to mod either lever or the face plate to use reserve. Also the fuel exit (port, nipple what ever your term is) is on the side making it interesting to connect to carb.

 Changing a petcock is one of the easier tasks to perform on a bike, I'd nix the vacuum for the traditional

1 hour ago, Dmouse said:

 Changing a petcock is one of the easier tasks to perform on a bike, I'd nix the vacuum for the traditional

Correct me if I’m wrong but can’t the traditional fail as well ? Leak on off ?

6 minutes ago, Markl5557 said:

Correct me if I’m wrong but can’t the traditional fail as well ? Leak on off ?

 Yup, it can. I have an E, mine failed, but the needle valve and seat was able to stop the flow of fuel. When my needle/seat failed on me, because I have the FCR, gas dripped on the ground and not into the motor. I've never owned a bike with the vacuum petcock, but just the way they are designed to work makes me not like them. The traditional petcock has a rubber gasket in it that can fail, but is easy to replace

My vacuum petcock failed once in over 8 years of owning the bike.

Replaced with a new stock petcock with the vacuum disconnected. Since then I have forgotten to turn off the  petcock several times in two years, flooding the crankcase 3 of those times.

So to me it hasn't been worth it. In the end it will depend on who you trust more, your mind or rubber.

Mine failed twice. Changing out the $16 per quart oil made it a nobrainer.  Finally changed the BSR to the FCR carb to stop the needle valve leak.

On 2/8/2018 at 7:08 AM, Gary in NJ said:

There are two types of vacuum petcocks on the DRZ; those that have failed and those that are gonna.

Ditto!

On 2/8/2018 at 8:08 AM, Gary in NJ said:

There are two types of vacuum petcocks on the DRZ; those that have failed and those that are gonna.

my bike is 18 years old and its never failed lol ... if it does i'll replace it .. i think its important to use it and actually turn it every now and then and also i consider it important to drain the float bowl if the bikes going to sit for more than a couple of days, it leaves fuel 'stacked' on top of that oring in the float valve if you dont and its not good for it .... but a manual valve will lead to the same problems because your going to forget to turn it off, and with the 'unvented' design of the cv carb, when that oring goes, and THAT for sure will sooner or later .. your crankcase will be petrol soup ...

Manuel Petcock? Ill take gay gardeners for 400, Alex.

How does the stock petcock have much to do with fuel getting into the oil?  Doesn't that mean the primary reason for concern is that seat in your carburetor?

I had a MX carb on my old DRZ, and the thing only ran on prime because it didn't have the vacuum line hooked up.  The bike sat all winter for months on prime, I rarely turn the fuel off on my vacuum fed bikes and even with the bike that only ran on full-open prime it didn't leak any gas..  What am I missing here or am I just getting lucky?  Or are we just trying to make sure we have two fail-safes, the petcock and the carb, to stop gas from getting into the motor when its not running?

 

I just feel like if you're getting gas in your oil you need to fix the petcock AND clean/repair your carb float / seat doohicky.  The 2nd option being the actual cause of the problem, and the petcock just being the delivery of it. 

 

If the gas getting somewhere is an issue, wouldn't it be a better idea to have some sort of quick-disconnect between the carb and gas tank?  To really make sure fuel isn't getting into the motor, and if the manual petcock fails it'll at least leak on the ground if the fuel line is disconnected. 

Edited by JJaySBK

250 miles on mine and not gonna wait. Did the swicth 2 days ago.

s-l400.jpg

Edited by kreator
1 hour ago, HeavyRotation said:

Manuel Petcock? Ill take gay gardeners for 400, Alex.

Lmao you have me cracking up at work

1 hour ago, cowpie said:

my bike is 18 years old and its never failed lol ... if it does i'll replace it .. i think its important to use it and actually turn it every now and then and also i consider it important to drain the float bowl if the bikes going to sit for more than a couple of days, it leaves fuel 'stacked' on top of that oring in the float valve if you dont and its not good for it .... but a manual valve will lead to the same problems because your going to forget to turn it off, and with the 'unvented' design of the cv carb, when that oring goes, and THAT for sure will sooner or later .. your crankcase will be petrol soup ...

I was told you don’t need to drain the float bowl if stored  ONLY if you use a very good gas treatment that helps prevent gasket seal wear in the carb there is a great mechanic down by me who clarified the whole thing in his opinion the petcock should be kept stock 

On 2/8/2018 at 0:32 PM, attuco said:

Mine failed twice. Changing out the $16 per quart oil made it a nobrainer.  Finally changed the BSR to the FCR carb to stop the needle valve leak.

16 dollors per qt ? That’s pricey I run Belray and it’s 9 a quart non synthetic ....

2 hours ago, HeavyRotation said:

Manuel Petcock? Ill take gay gardeners for 400, Alex.

Another joke about petcocks, I heard from a guy that had a radiator repair shop years ago.  When you are young, it is a petcock.  When you get old, it is a draincock.

Always wondered about this. I've had other bikes w/vacuum petcocks & no issues. If it ain't broke, don't fix it. If it does break... Well, my bike is new to me but 10 years old. I'll just replace w/the same petcock since the OEM lasted that long, thanks.

YMMV if you've changed your carb. I'm still running the stocker.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now