XJ650RJ Seca Build

Thanks I’ll have to double check where I got the info to buy the plugs as you are correct that I do have the BP8ES.
I last tested the compression about a month ago.
#1 = 150
#2 = 140
#3 = 140
#4 = 150

No signs of anything coming out of the exhaust.

 

Picked up a set of correct NGK plugs on my lunch break. I’ll check the gaps and install tonight after work.

 

So the color tune was making me pull my hair out. I'm having similar results to some other people on this site, hook it up to a warm engine, turn the air/fuel mixture screw all the way to 1 side and then all the way to the other, and no change in the color of the flame... So I'll have to come back to that later on.

After hooking up the correct spark plugs (*facepalm*) and some "attempts" to adjust the air/fuel mixture the bike preforms a little better. It has a quicker feel on the throttle. Not quite as good as it should be, and the idle is still slower to fall than it should be. I guess I'll just keep at tinkering each day until I feel i'm starting to make it worse.

Since I can't get the color tune to work, I plan on trying to put some miles on the new plugs so I can read the plugs the old-school way.

 

After a morning of research and looking at old notes, I’m suspecting that I might have a float level issue which may be contributing to my lean mixture. Since my bike is lowered in the front due to the front end, I’m suspecting that I need to retest my wet float levels while the carbs are on the bike, vs on the bench. I’ll do 2 versions for the test,
1. On center stand
2. Off center stand on 2 wheels.

Hopefully this will allow me to rule out that as an issue, or lead me to pull the carbs yet again.

 

After puling the carbs off the bike again and setting them on my carb rig and 7 rounds of float level testing, I have successfully gotten 1 carb in spec. Somehow no matter how I adjust the tang, up, or down the float levels stay the same on the other 3 carbs, which is too low. i'm measuring 7mm vs. the 3mm that needs to be in spec. I'm at a loss.

I know the PO replaced the float needles with an unknown set. I'm guess that these were a cheap eBay set. Only thing I can think of is to replace them with a set from Chacal to confirm that these are intact good.

-___-

 

Sounds like a solid plan there. If the needles are too long, you'll have a hard time if at all getting the level higher. You'll sleep better too knowing what's in there.

 

Waiting for my order from chacal to come in

 

Chacal to the rescue. Ordered my new needles on Friday night and got them delivered Sunday. So installed them today. Only took 1 round of adjustments to get all 4 float levels perfectly in spec. Now the tuning process should be a little easier this time around.

 

So progress is continuing to be made. After a minor idle adjustment on the carb, the bike starts right up and holds and idle much stronger than it did before. Which makes sense with now having the correct fuel level in the carbs. The throttle response has improved as well.

However, it’s still a little slow to return to idle after letting off the throttle. And after 10 minutes, the idle slowly starts to increase. So I guess I need to trace down an air leak somewhere.

I’ve tried the propane truck before with no success, and I’m hesitant to spray carb cleaner around the freshly painted engine -____- as well as my colortune is still showing the same color flame, regardless of how I change the air/fuel mixture.

 

So, after some work on the bike, I thought that the source of my air leak was due to a gap in the airbox lid. However i have been informed that this is not the case. So after continuing to spray carb cleaner all around the carbs (from the intake boots to the airbag boots) i'm unable to cause an rpm change (either up, or down). So i'm at a loss of what to do next to get the bike working.

For the first few minutes of a ride, the bike feels great. It pulls super strong, the only issue is that lack of engine braking due to a slow fall of the rpms back to idle. after a few minutes on the bike, the bike wants to idle up at around 2-3K. I can sometimes use the clutch to pull the rpms back down to around 1k. but then it will slowly start moving back up.

 

In my experience this can be cured tweaking the mixture screws richer. You said this helped a bit a few posts back. Go another 1/4 turn and resynch.

 

wd-40 can be used to test for air leaks.
when you color tune again try adding a littler choke to see if that changes the color helps to confirm air leaks.

and on another unrelated issue on your tci the connector from the pickups do you have 1 or 2 black wires from the pickup harness to tci ( wiring diagram shows 2 but I only have one)? I just want to confirm sub harness to be sure the pickups are correct to the (my) 650rj

 

Thanks

I’ll have to try all the fluids next time. I used carb spray and electrical cleaner and propane and got no results from the test. I’ll try wd40 and see what happens. I haven’t played with the choke at all. Even when starting I don’t use it. (It’s a constant 70-80 in San Diego)

Regarding the connections on my harness, I believe there is only the 1 black wire. I double checked my wiring diagram (page 4) and only noted 1. But I’ll take another look and confirm.

 

just checked my fsm and it confirms 1 wire as you stated . I thought I lost the manual on my computer

 

Have you performed a vacuum synch on the engine yet?

 

Yes I have. For some reason my carbtune is actuating strange to where I’m not getting a proper reading. (After putting in the resisters) turning it upside does help a little. I’m goimg to try to synch again, and then try to get ahold of another gauge, and reset the idle mixture screws and keep a log of every action being taken on the bike. This will help me keep track of exactly what’s been done.

 

If you are using the Carbtune Pro "sliding rod" synch gauge, the resistors should not be necessary.

 

So many conflicting statements on this site. Haha I will try without the resistors and compare the results. Thanks for the feedback.

 

this sounds to me like you're only running on 3 cylinders until it gets fully warmed up. next time you start it from cold, check that the pipes get hot evenly.
were you adjusting the idle after a good long ride?

 

I had that issue, but it’s been resolved. However I will double check tomorrow evening when I work on the bike to make sure all 4 are still warming up together.
Gotta rule out the simple stuff.

I’ve also ordered new fuel and vacuum lines from chacal with new clamps to help rule those out as any causes of my issue.

 

I just glanced the thread over but I’m leaning towards two areas.

One, did you replace the intake boots? I got some aftermarket ones and they delaminated in just a few days after install. Make it hard to start, unable to idle well, and colortune was ineffective. How are the caps on the intake boots? Are they clamped tight?

Two, I don’t see any mention of you doing a through carb rebuild. I see you mention that the PO replaces needles and you replaced them again. You might have internal issues causing it to run lean or have air leaks in throttle seals etc.

 

Thanks for the feedback.
Yes I’ve replaced the intake boots with the oem ones from chacal. (Not cheap) And I’ve replaced the trottle shaft seals during the rebuild. I’ve also used multiple sprays to test for vacuum leaks with no results.

Regarding the caps and clamps, they are also new replacements from chacal. However I’ve noticed that even with the clamps on, with a set of players, I can grab onto the top of the rubber clamp and pull the rubber and clamp off the intake hose. However when spraying carb cleaner to test for leaks, I’m not getting an rpm increase.

 

Mixture screws & synch.

 

Cool, yeah I had to go the OEM intake route as well. Not cheap but should last another 30 years. I had the same experience with the vacuum caps as well, can pull off with little effort with pliers but they seem to seal just fine and have not moved in 1.5 years.

Kinda running out of ideas. Did your slides pass the clunk test? Maybe they are hanging up. In your vid your throttle response sounds slow too when opening the throttle.

 

I also just watched your video showing the carbtune hooked up, those readings are way low at idle. You definitely have some air getting in somewhere or something else going on.

I'm no carb guru but I will put this out there, mainly because I'm wondering. I'm wondering if you have an issue with the idle circuits in the carbs and you're not actually running on them. Does turning the choke (enrichener) on make any difference on the idle speed? It only comes into play at idle and just off idle. If there is an idle circuit problem you might have the idle stop screw in too far just to keep it running, effectively "achieving" an idle.. This would keep the throttle plates open further and lower your vacuum readings when attempting to sync.

 

Yes they’ve passed the clunk test. While having them on my carb stand when wet setting carbs I compared the clunk speed of all 4 carbs and they all were the same.

I’m going to try to carbtune again today (it was too hot to work outside without any shade since I’m working on an open parking lot). I currently have the resistors in the carbtune hooked up based on an old recommendation but will try without them to see if the reading is better.

For th idle circuit, I actually haven’t been using it lately. But I’ll confirm what effect it has.

I’m thinking of starting back from square 1 and filming everything for reference and keeping a detailed log of all adjustments.

Start placing your bets people on what the issue is haha.

 

They are there to "smooth" out the readings, not increase/decrease the amount of vacuum measured. The rods will be bouncy without the restrictors.

If you're not using it, then it's not going to idle nor can you tune it I think you meant choke.

 

Oh haha that’s what happens when I try to multitask at work... Ill work on it tonight and report my results.

 

First off, thanks everyone for the feedback. Right before I left work, I re-read the recent posts to get back into the mind-set of motowork instead of database work. Once I got home I only had about 30 minutes left of light, so I fired it up and took it around for a quick few laps around the neighborhood to get it warmed up and proceeding to re-sync the carbs with the resistors removed in the carbtune. Such a difference, I was actually able to read the carbtune and see the difference a turn of the sync screws would make. So I was able to dial in all 4 carbs together and the bike idled better. I wasn't too badly off beforehand, but every little bit counts. Taking it for another lap around the neighborhood, I could feel the engine braking actually kicking in. Its still a little slow to return to idle but it does a lot better. And after a future round of colortuning, I should be in a better place.

During the whole process, I also tried spraying carb cleaner and electronically cleaner around all throttle shaft seals, all intake boots, intake boot rubber clamps, and airbox clamps with no change in rpm.

Ultimately, I think my idle was set a little too high to start, and in combination with the 4 carbs being out of sync, this caused the idle to be very hard to return to normal as each carb was competing against each other.

Next days plan:
1. Colortune
2. re-carbtune
3. Possibly color tune again,
4. Install new plugs (So I can get a good reading of work)
5. Cross fingers
6. Suit up and enjoy a ride along the coast this weekend.

 

YES!!

I would recommend executing your plan in the following order:

1. Install new plugs (So I can get a good reading of work)
2. Colortune cylinder #1
3. re-carbtune (synch) entire engine
3. Colortune cylinder #2
4. re-carbtune (synch) entire engine
5. Colortune cylinder #3
6. re-carbtune (synch) entire engine
7. Colortune cylinder #4
8. re-carbtune (synch) entire engine
9. Suit up and enjoy a ride along the coast this weekend.


No longer necessary:
10. Cross fingers

 

So I am curious about this. In your first video without the restrictors the gauge indicators fluctuated wildly and it was pretty much useless. Note that it is important to add the restrictors at the proper point (near the engine) so that the open hose downstream from that actually helps dampen the reading by acting as a storage capacity for the vacuum reading. You can read about it here:

http://www.carbtune.com/inst.html

An excerpt from above:

"Set-Up

Damping. The restricters must always be used.

Without restricters the rods will fluctuate wildly. There are two components to the damping.

1. The small amount of friction between the rods and guides which is overcome as soon as the pulsating vacuum of the engine is connected. This friction can vary from tube to tube in the Carbtune and is not a fault.

2. The air-flow restricters that fit inside the rubber tubes and damp the fluctuations. There will always be a small amount of fluctuation and this is necessary for the gauges to work properly. Do not oil the rods."

 

So hooking up the colortune again provided unclear results. For cyclinder 1&2 I could adjusts the mixture screw all the way in vs out and not see a change in the color of the flame. So I reset to where I was at. I looked at the old plus and leaned out carb 1 a hair, and richened carb 3 a hair and re synced the carbs.

I’ll put some miles this weekend and adjust based on the plug reading.

 

And you opened up the enrichment circuit momentarily to verify a change in the colortune color to yellow?

 

No I did not, I only adjusted the mixture screws on the 2 carbs. But I guess that would make sense to open up th me “choke” / enrichment circuit as it would have a dramatic impact on the mixture going into the engine.
I will try that 1 more time and see what happens.

 

Ugggh. Sounds like the mixture circuit passages are stilled a problem on those carbs. Hitting the choke as Rooster53 suggests will confirm this theory (assuming the choke circuits aren't plugged, too).

 

The test will confirm. I feel like I will have to take the carbs off the bike again and re-clean those.

 

Hey mate loving the build!
Just bought a 650 seca here in Australia! Just wondering what bars you are running? Planning on doing something similar with the seat and bars. Cheers mate!

 

Awesome! Be sure to show us photos of your build. I picked up a set of biltwell tracker bars. I’m not 100% sure on how they would fit/look with the stock triple tree clamp as I have a custom one for the gsxr swap.

 

Yea will do for sure! I've taken on your advice and I'll definantly have videoing vas much as possible too!

I'd hate to be that guy asking what everything you have is but those mufflers look insane! What are they

 

They are the stock mufflers actually. I guess the us seca had a different version vs other countries.

 

Oh righto!!!

Yea we only have Seca's here so it's just labeled as xj650. Anyways... looking forward to more of your build

 

So after putting about 100 miles on the bike, I swapped out the spark plugs. looks like I need to richen up the mixture a little. After a few different rides on the bike, I've noticed that it takes a little bit of time to warm up. around 5 minutes to keep a strong idle. But after cruising on the freeway for a bit, it idles nice and strong.

Hoping a little more fuel in the mixture will get me more dialed in.

Plugs 1&2


Plugs 3&4

 

hey man. love the build. Just moved to san diego in july. i got an 82' xj550 with a 2006 r6 front end. its not even close to done but i think that eBay gauge might be the ticket. Any updates on how your bike is running?

 

Oh awesome. Another San Diego xj rider. What part of SD are you in?
The eBay garage is worth the few bucks. No issues with that so far.

I’m still having some issues tuning the bike. I need to find some time to re go through everything and find the cause.

 

Finally jumping back into the build this weekend. I found a local shop in San Diego that is a community garage. For a monthly fee, I take in the bike and have full access to everything I could possibly need. Ultrasonic cleaner, vapor honing, welding, work bench setups. As well as a community of other enthusiasts to check in with. That combined, with this forum, I should be able to get this bike dialed in as perfectly as possible.

So in preparation for this weekend, I ripped the carbs and front calipers off the bike and and doing a final rebuild on both. The carbs have not been able to be dialed in yet. Im suspecting an issues with the enrichment circuit, and possibly the air/fuel mixture screws. So i have broken the rack down to every component and will ultrasonically cleaning these tomorrow before a final rebuild. I've also taken the calipers off as I had slight drag on the front wheel. With a wheel stand on the front wheel, I could get 1/4 - 1/2 of a turn while trying to free-spin the front wheel. Those will also go in the ultrasonic cleaner.

While I had the carbs off, I noticed this on the inside of my new carb manifolds. I bought the OEM spec manifolds from Chacal. (not the cheap eBay ones). Does this look "normal"? or is this due to a bad gasket and the manifolds are getting too hot and bubbling? Carbs 3 & 4 did not appear to have this issue.
carb 1


Carb 2

 

Sure doesn't, in fact that looks like what the aftermarket manifolds do. Is that way just on that manifold? And does it appear to be "bubbled" or melted?

 

I’ll take off the manifolds tomorrow and inspect closer. I recently installed them, so there shouldn’t be an issue with taking the bolts out.
I’m hoping they are not toast as they are expensive.

 

Once you get them off and inspect them, send me an e-mail and let's see what we can figure out!

 

https://imgur.com/a/6plyA
(sorry they are out of order)

So after some inspection, it looks like only 1 & 2 have gone through some damage. I see cracks on the backside, and bubbles in the middle. I actually compared these to the cheap boots I had previously and the cheap ones look better.

 

So on a positive note, I got the carbs ultraonicslly cleaned today as well as cleaned my brake calipers and my second donor set. 1 piston was sticking so now I can reassemble everything and get it as good as new.