Hi! New to the forum, but happy to be here.

Background before I get to my question
I just bough a new-to-me 1989 GS500e that is a bit of a Frankenstein... The engine is from a gs500f, I believe a 2006. I know this because the tachometer doesn't work, since the 500F uses a digital signal and my tach is analog. The carbs, however, are from the older models. The bike was running when I bought it (a little rough), but then it started stalling out, and now it wont start at all. I blamed this on the old gas, but since draining and putting in new gas it is still wont start. It does turn over, though. The gas tank is getting a little rusty on the inside, so i know that that must have made its way to the carbs. I actually hydro-locked my engine trying to start it, but I was able to rectify that by removing the spark plugs, cranking the engine, and watching the water (gasoline actually) show. I'm currently letting it air dry before I try again.

It's probably my best bet to clean the carbs, but I know that this may happen again with the tank being rusty.

This bring me to my actual question
Has anyone had any luck installing an in-line fuel filter? I know that I should use one of the lawn-mower style filters, since the bike's system is gravity fed and no fuel pump like a lawn mower's. I would install it after the petcock and before the carbs. Do you guys think this would work, or should I not care about the rust in my tank? Oh, and i might have played with the idle screw a bit, and now I have no clue if it is in a good working position or now... Any way to check that without starting the bike?

Also, this is my first motorcycle lol. And first time working on anything with carbs. I do have some mechanical know-how from DIYing on my car, so I am a little comfortable doing the work myself, though I am doing all kinds of things I've never done before.

Don't bother.

In my experience they cause more issues than they solve.  There's a screen inside the tank anyway...


Be warned that the new model carbs use a slightly different boot than the old model, so old carbs won't simply bolt on to a new engine unless the boots were also swapped.
But I want to say you would notice if the boots were a little "off".

I think your compatibility issues go further then the tach my brother the Throttle Positioning Sensor off the newer bikes controls timing as well unless i am mistaken.

I had massive and strange issues when i tried the reverse, a '97 motor into an 06 bike "just put it in it'll work just fine" is what the guy at the shop who sold it to me said, the sack of shaZam!

as it turned out I would have had to put in carbs and linkage from an older gs I ended up picking up a motor from an 04.

Hopefully for your sake the reverse is not true

Thanks for the heads up on compatibility! I know the bike was ridden for a little while before I had it, so I think all of those little details must have been taken care of at the time of the install. I'm pretty sure the bikes carbs need cleaning, first and foremost, though. I got it off a friend who let it sit for a year without properly winterizig it, and then i let it run on old gas...

Quote from: Jagged on May 13, 2017, 07:34:16 PM
I think your compatibility issues go further then the tach my brother the Throttle Positioning Sensor off the newer bikes controls timing as well unless i am mistaken.

I think you are.  I have no first hand experience with the 2k1+ bikes, however ignition timing is fixed and there's no ECM so there's no reason I can think of to have a TPS.

There is a TPS on the RH carb on the later models. I would say it had nothing to do with the ignition timing though. There is also a electrically controlled device which is linked into the vacuum lines and opens and shuts a valve on the top of the carbs. This link explains it - http://gstwins.com/gsboard/index.php?topic=56601.msg849249#msg849249

Shift-E, try checking the float height using the tube method -  http://www.bbburma.net/FloatHeight.htm
You might have a float needle stuck open.
Drain your float bowls and see what sort of crap has built up in there. Maybe put the fuel tap on prime for a few seconds to help flush it out.
Also, tapping the bowl with something hard may help it seat otherwise it is a carb off job.

Good luck

Quote from: Sandgroper57 on May 13, 2017, 09:38:28 PM
There is a TPS on the RH carb on the later models. I would say it had nothing to do with the ignition timing though. There is also a electrically controlled device which is linked into the vacuum lines and opens and shuts a valve on the top of the carbs. This link explains it - http://gstwins.com/gsboard/index.php?topic=56601.msg849249#msg849249

That's super weird.  Glad I stuck with pre-2k GSs 

Any idea what the TPS even does?  Ignition is still controlled by the signal generator rotor and it's not an EFI bike so the timing is set mechanically and is more or less permanent.
Unless the TPS's job is tied solely into those vacuum doohickeys.

That float trick is nifty. Though I do think its best to just take the carbs off at this point because i think something actually may be stuck.
When set to pri (before i knew what it was) i ended up having gas pouring out the airbox drain hose. It really freaked me out at the time until I found out what it was lol

Quote from: Watcher on May 13, 2017, 09:46:41 PM
Any idea what the TPS even does?  Ignition is still controlled by the signal generator rotor and it's not an EFI bike so the timing is set mechanically and is more or less permanent.
Unless the TPS's job is tied solely into those vacuum doohickeys.

I'm guessing it is to sense when the throttle is shut off then the valves are opened. But, I could be wrong (could also be wrong about the ignition timing as well). There doesn't seem to much info to be had for this setup. On the plus side though, it all works. I haven't ridden an earlier GS so have no reference as to better or worse performance but I am happy with the way the bike runs.

Quote from: Shift-E on May 13, 2017, 10:13:49 PM
When set to pri (before i knew what it was) i ended up having gas pouring out the airbox drain hose. It really freaked me out at the time until I found out what it was lol

It means your float needles are leaking.

Do yourself a favor and get a new pair of float needles, a pair of 40 pilot Jets and 125 mains, and a complete set of all o rings including the ones for the idle mix needles and then pull the carbs, clean everything, replace the float needles and the o rings, replace the intake boot o rings and then set the float height and put it together. Set idle mixture and speed according to the wiki. 2 hours work and get it all done at once. Otherwise you'll be on here a hundred times with this and that little problem until you wind up doing this all anyway but spend 4x as much on parts​ and have the carbs apart four or five times.

Quote from: mr72 on May 15, 2017, 04:44:34 AM
It means your float needles are leaking.

Do yourself a favor and get a new pair of float needles, a pair of 40 pilot Jets and 125 mains, and a complete set of all o rings including the ones for the idle mix needles and then pull the carbs, clean everything, replace the float needles and the o rings, replace the intake boot o rings and then set the float height and put it together. Set idle mixture and speed according to the wiki. 2 hours work and get it all done at once. Otherwise you'll be on here a hundred times with this and that little problem until you wind up doing this all anyway but spend 4x as much on parts​ and have the carbs apart four or five times.

Thanks for the tips! I figured i'd need to do a carb rebuild with gaskets/orings/float needle. Didn't think about the jets.

So correct me if I'm wrong, but youre saying all I will need is 2 of these kits: http://www.ebay.ca/itm/K-L-18-9310-Suzuki-GS500E-DR250S-DR250SE-Lower-Bowl-Carburetor-Repair-Kit-/401275296577?hash=item5d6ddf1b41:g:zD0AAOSw42JZAnQX&vxp=mtr

PLUS Jets numbered 19 and 31 on this parts diagram: http://www.partzilla.com/parts/search/Suzuki/Motorcycle/1989/GS500ET/CARBURETOR/parts.html

While also looking at the diagram, i'm assuming the carb kit includes numbers 26, 27, 29, 33, and 34. Does that sound right? I'f I can source them individually and it be cheaper, maybe I'll go that route vs an ebay kit.

Anything else I should pick up while I'm at it?

Quote from: Shift-E on May 15, 2017, 05:52:03 AM
Thanks for the tips! I figured i'd need to do a carb rebuild with gaskets/orings/float needle. Didn't think about the jets.

You want to upsize the jets since the bike is jetted lean from the factory. And the pilot jet is tiny and easily clogged, easier to replace than try to clean it.

You want to run a wire through the pilot orifice once the jet is out.

Quote
So correct me if I'm wrong, but youre saying all I will need is 2 of these kits: http://www.ebay.ca/itm/K-L-18-9310-Suzuki-GS500E-DR250S-DR250SE-Lower-Bowl-Carburetor-Repair-Kit-/401275296577?hash=item5d6ddf1b41:g:zD0AAOSw42JZAnQX&vxp=mtr

PLUS Jets numbered 19 and 31 on this parts diagram: http://www.partzilla.com/parts/search/Suzuki/Motorcycle/1989/GS500ET/CARBURETOR/parts.html

You also need #20 o rings likely not in the kit.

Quote

While also looking at the diagram, i'm assuming the carb kit includes numbers 26, 27, 29, 33, and 34. Does that sound right? I'f I can source them individually and it be cheaper, maybe I'll go that route vs an ebay kit.

You can definitely source them cheaper but not by a whole lot. You can get everything you need for a little more than the price of one kit to do both carbs. You need to get the float needles from somewhere and they are about $12 each or so. You may not need the float needle seats at all but they often come with the needle valves. Make your life easy to and buy the kits and supplement with o-rings from thisoldtractor or the dealer.

You will also need to find a #20 o-ring (from the diagram) and to head off future vacuum leaks and while you have it apart, I would also get a pair of PN# 09280-40010 from this site:
http://www.thisoldtractor.com/for_sale_dr350_orings.html

BTW you can get some of the other o-rings from here.

SPN# 13295-29900   
SPN# 13374-35C00   
SPN# 13374-46710   

Only one they don't have is the o-ring that goes under the vacuum port on the top of the carb.

By the way DO NOT SPRAY CARB CLEANER ON THE CARBS while they are fully assembled. It will ruin the rubber diaphragms under the carb caps. So you need to remove the rubber diaphragms and tear down the carbs all the way removing other rubber parts before hitting it with carb cleaner.



Anything else I should pick up while I'm at it?
[/quote]

Great! I will definitely look into getting all the appropriate o-rings. It looks like this carb kit comes with 4 o-rings, so I feel like #20 is included in that list perhaps?

So for the Jets, would I simply buy these and swap them with the originals?

Main Jet:
https://fortnine.ca/en/ebc-mikuni-slot-head-style-main-jets

Pilot Jet, which of these two would I use for our carbs?
https://fortnine.ca/en/ebc-pilot-jets-mikuni-style-n224-103
https://fortnine.ca/en/ebc-pilot-jets-mikuni-style-vm28-486

Quote from: Shift-E on May 15, 2017, 08:23:41 AM
Great! I will definitely look into getting all the appropriate o-rings. It looks like this carb kit comes with 4 o-rings, so I feel like #20 is included in that list perhaps?

I doubt it. I bet that 4th o-ring is for the vacuum port on the top of the carb. Most people overlook the mixture needle o-ring (#20).

Quote from: Watcher on May 13, 2017, 09:46:41 PM.................................That's super weird.  Glad I stuck with pre-2k GSs 

Any idea what the TPS even does?...................

You missed the best GSs ever made, the 01-02 models.  They got the new 3 circuit carbs and no pollution changes except a retarding of spark at idle only.  I put 80k miles on a 97 and 100k miles on a 02. Rode them both the same day to compare a few times after the toralled 97 was fixed.  The 02 was smoother and pulled stronger thru out the mid rpm ranges although I felt the 97 was a bit stronger at the top  end.

2ND AIR (GS500F E33 / GS500FK6 E3 / GS500FK6 E28)

Above from 04-06 parts list, 2nd air with TPS was on E33 only for 04 and 05 and was added to E3 in 06.  E33 California and E3 US 49 states.

Ah, I found the proper pilot jets: https://fortnine.ca/en/ebc-pilot-jets-mikuni-style-n151-067

Yeah but those are quite expensive. Could be a Canadian thing.

I paid about $5-6 for each pair of jets I bought.

BTW in the USA the stock pilot is 37.5 and the next step up is 40. The stock main is 122.5 next step up is 125. Presumably the same in Canada. I recommend making the one-step-up jetting for both if you are keeping the stock air box (which is also recommended). I'm running 40/127.5 which is brilliant but I have a slip on Yoshi muffler. Bike ran fine with 125 jets too.

I think it is a Canadian thing, plus the fact that the packs come in a minimum of 4. I could order from the states, but shipping currency conversion completely offsets the savings.

I'm assuming I just need to put in the jets as a straight replacement, and that they shouldn't require anything extra?

Quote from: Shift-E on May 15, 2017, 11:36:53 AM
I'm assuming I just need to put in the jets as a straight replacement, and that they shouldn't require anything extra?

That's right.

But while you have the pilot jet out it won't hurt to run a wire through the inlet orifice at the bottom of the pilot jet hole to clear any junk that might be in there before putting the new one in.

Quote from: mr72 on May 15, 2017, 12:36:42 PM

Quote from: Shift-E on May 15, 2017, 11:36:53 AM
I'm assuming I just need to put in the jets as a straight replacement, and that they shouldn't require anything extra?

That's right.

But while you have the pilot jet out it won't hurt to run a wire through the inlet orifice at the bottom of the pilot jet hole to clear any junk that might be in there before putting the new one in.

Thanks for all the help!

I know that Watcher up above mentioned not to worry about an in-line fuel filter. What are your thoughts on adding one in, since my gas tank is getting rusty. Would it benefit or act more like a restriction? Or is it simply overkill for no reason?