Jet Block Gasket

Got questions? We got answers....
Post Reply
coasty
Supporting Member I
Supporting Member I
Posts: 19
Joined: 06:15 am Aug 30 2016
Country: New Zealand
Location: New Zealand

Jet Block Gasket

Post by coasty »

Our 05 KDX200 runs ragged at low revs, smokes excessively and was using gas at an alarming rate, it has a Gnarly pipe & a V Force 3 reed block, jetting was 48 / 160, we changed the pilot to 45 which helped considerably, I checked the float level and it was about 18 mm which is at the lower end of adjustment but still within spec, but you don't have to lean it far over to the left before gas starts poring out the overflow, I have searched the forums for answers before I drop another jet size and the " jet block gasket" seems to be something to try next, but looking on the partszilla carb picture I can't see a "Jet block Gasket" listed anywhere ? can someone point me in the right direction here please ?
cheers
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14047
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Re: Jet Block Gasket

Post by KDXGarage »

Sudco. It is NOT something you will get from Kawasaki.
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
User avatar
bufftester
Platinum Member
Platinum Member
Posts: 3455
Joined: 06:03 pm Oct 31 2012
Country: USA
Location: University Place, WA

Re: Jet Block Gasket

Post by bufftester »

At 18 mm your float is high, so it won't take as much to overflow, best to get it as close to 19 as possible. Sudco best source, the Keihin p/n is 1202-834-2000, the Sudco p/n is 021-532, price runs about $4 USD.
coasty
Supporting Member I
Supporting Member I
Posts: 19
Joined: 06:15 am Aug 30 2016
Country: New Zealand
Location: New Zealand

Jet Block Gasket

Post by coasty »

Thanks for that, I'll try and pick one up over here, failing that I'll order one from the US and reset the float height when I install it, then I can carry on with the jetting guide which is excellent by he way, cheers.
JL4049
Member
Posts: 86
Joined: 06:25 pm Jun 04 2016
Country:
Location: Eastern Victoria, Australia

Re: Jet Block Gasket

Post by JL4049 »

I had similar issues when I first got my kdx. I installed an inline fuel filter and that solved the needle constantly getting held off the seat, then I set the float height at 19mm, now it only leaks fuel when tipped way over. The overflow tubing only shows fuel around it now when doing jumps r riding rough/steep hills. I'm getting 125k plus out of a tank too in the hills. Jetted 45 pilot and 158 main this weekend and runs really well, followed my young fella around for a couple of hours and no spooge running down exhaust. I could probably go leaner yet but some of the hills I ride can be several minutes of WFO throttle, so will see how it goes on the next bush ride before I do.
coasty
Supporting Member I
Supporting Member I
Posts: 19
Joined: 06:15 am Aug 30 2016
Country: New Zealand
Location: New Zealand

Jet Block Gasket

Post by coasty »

Right, this is where we are up to,
I couldn't find a jet block gasket in NZ so I got in touch with Sudco who as you say can do one for $4.41 USD, unfortunately postage will be $30 to $35 USD which works out to about $60 NZ, so before I order one I really need to inspect the old one to see if does actually need replacing, when I went to pull the Jet Block out I find it is held in by tricky little screws which I don't have a tool for, so stuff it, in goes the new 42 pilot jet, reset the float to 19mm and out we go for a test ride, this improves the running of the bike again, less smoke and runs cleaner but still runs ragged at low throttle (0 to 1/4), it is fine through the rest of the throttle range and actually goes really well.
My next step will be to get the proper tool to pull out the jet block and see if the gasket needs replacing or not, I am starting to think I actually need a new carb, can anybody point me in the right direction for a new carburetor supplier ? or am I overreacting and just need to keep working through this ?

thanks again for all your help
ohgood
Supporting Member II
Supporting Member II
Posts: 925
Joined: 10:00 am Jan 04 2014
Country:

Jet Block Gasket

Post by ohgood »

coasty wrote:Right, this is where we are up to,
I couldn't find a jet block gasket in NZ so I got in touch with Sudco who as you say can do one for $4.41 USD, unfortunately postage will be $30 to $35 USD which works out to about $60 NZ, so before I order one I really need to inspect the old one to see if does actually need replacing, when I went to pull the Jet Block out I find it is held in by tricky little screws which I don't have a tool for, so stuff it, in goes the new 42 pilot jet, reset the float to 19mm and out we go for a test ride, this improves the running of the bike again, less smoke and runs cleaner but still runs ragged at low throttle (0 to 1/4), it is fine through the rest of the throttle range and actually goes really well.
My next step will be to get the proper tool to pull out the jet block and see if the gasket needs replacing or not, I am starting to think I actually need a new carb, can anybody point me in the right direction for a new carburetor supplier ? or am I overreacting and just need to keep working through this ?

thanks again for all your help

for the odd screws that hold the jet block in place, just use a hack saw (or dremel tool) to cut a slot across them. then you can use a common head screw driver to get them out. they are pretty tight, so you might need to warm up with carb body in hot water or similar to help break the bond. once you get the jet block off it's pretty easy to see if the gasket is collapsed or not. it usually fixes all the "way too rich!" conditions.

mine was the exception, and i ordered a new carburator from jets-r-us for $170 shipped. the bike now runs incredibly well, and responds to EVERY nuance in tuning that I apply to it. in the past with the old carb the adjustments i made resulted in sporadic and unpredictable results. sometimes the air screw made differences, sometimes it did not.

BUT

before you dig into paying a LOT of your NZ money for a new carb, make sure your KIPS is functioning properly. it's a common source of problems with bikes that aren't cleaned, or run overly rich and clogged up with carbon. when they are functioning, the bottom end is extremely smooth and predictable, when they are not, it's like riding a 125: no bottom end, and rips up top
coasty
Supporting Member I
Supporting Member I
Posts: 19
Joined: 06:15 am Aug 30 2016
Country: New Zealand
Location: New Zealand

Re: Jet Block Gasket

Post by coasty »

Thanks for that ohgood, I will investigate The KIPS next before shelling out for the price of a new carb which is about $250.00 NZ + shipping which can be anything from $20 to $120, also setting the float to 19mm sorted the overflow issue so progress!! cheers.
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14047
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Re: Jet Block Gasket

Post by KDXGarage »

Isn't the jet block held in with security Torx fasteners? Maybe you can find a bit for sale and use it.
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
coasty
Supporting Member I
Supporting Member I
Posts: 19
Joined: 06:15 am Aug 30 2016
Country: New Zealand
Location: New Zealand

Re: Jet Block Gasket

Post by coasty »

Yes, looks like a Torx head screw with a pin in the middle, one of the boys at work should have a tool, we have a ride this weekend so I'll pull the carb off Sunday night and we'll strip and inspect it on Monday, there is also the possibility of borrowing another carb off a mate who has FIVE KDX's (legend). The bike has had recent top & bottom rebuild which is why we bought it so we are thinking that the KIPS should be OK.
coasty
Supporting Member I
Supporting Member I
Posts: 19
Joined: 06:15 am Aug 30 2016
Country: New Zealand
Location: New Zealand

Re: Jet Block Gasket

Post by coasty »

So, I rode on Sunday and although it goes well in the mid range and top end, it is actually really hard to ride because it runs so ragged down low, I pulled the carb apart and the Jet Block gasket is in good condition so that's not the problem, I measured the bore of the carb on the engine side and it is 36mm. I would of thought it should be 35mm ? any idea what my next step should be, or "take it to the shop " can I check the KIPS without taking the engine apart ?
Thanks in advance , I really do appreciate all the help and advice.
Davenay67
Member
Posts: 59
Joined: 05:42 pm Apr 06 2014
Country:
Location: Lisle, IL

Jet Block Gasket

Post by Davenay67 »

Be cautious of a jet block gasket which looks OK.

Mine did too, but I went ahead and replaced it anyway because I had bought a new one in advance. The difference with the new gasket installed was night and day.
coasty
Supporting Member I
Supporting Member I
Posts: 19
Joined: 06:15 am Aug 30 2016
Country: New Zealand
Location: New Zealand

Jet Block Gasket

Post by coasty »

I took the bike to the Local Kawasaki dealer who checked it over and found the Power valve was set one tooth out in the timing, so the PO who did the rebuild assed it up when he reassembled the engine, the bike now runs much better down low and the transition from low revs & low throttle to the mid range & WOT is much less violent and it is far easier to trail ride, it is still not perfect but far better, I will now have to start the jetting guide again from the beginning,
Did a bit of a trail ride around our little farm this morning and the KDX has never run so good but still a little ragged down low so I have asked my mate who is coming over from Seattle in January to bring me over a NEW carb from Jetsrus as the don't ship to NZ, hopefully this will clean it it up 100%.
On the plus side my XR250R has been on the receiving end of my new found jetting skills such as they are and is running great !

Thanks to everybody for your help & input, very much appreciated
Post Reply