Vid of my bike running after carb rebuild. Ideas?

Im pretty quiet in the vid.

but the bike is louuuud and crappy running... As you can see, its cold and i started without enrichment on. it idles poor..

i know what you're going to say.. wheres the airbox? well... i have pods.. the bike came with no filtration when i got it.

i tried backing out the mix screws and starting and it continues to run this way. right now its probably 5 1/2 - 6 turns out. Trust me, it runs the same as if it was 2 1/2 turns out.

all orfices are clean!.. 1.5 cans or carb cleaner and the little straw..
Heres what i did:
- replaced ALL pilot fuel jets
- soaked mix screws, pilot air jet, main jets in brake cleaner and carb cleaner.
-replaced all needles and all needle seats with beanies and seals.
-replaced all mix screw o-rings, metal o-rings and springs.
-bench sync'd twice.
-dry set and wet-set floats multiple times.

anyways, heres the vid. ideas?? Thanks

http://youtu.be/2KW8LhpOVN8

 

I would assume the idle speed screw isn't in too far, is it? Other than that I didn't see throttle shaft seals in your checklist. If those are leaking you will get a high idle. Now I don't know how much the open carbs in the video will affect the idle but I wouldn't suspect that much. With the motor running spray some carb cleaner on the throttle shafts and see if the rpms rise. I suspect it will. If that's the case you need to replace the seals.

http://www.xj4ever.com/hitachi%20thrott ... 0seals.pdf

 

Nope. I made sure the knurled idle screw isnt too far in. It's not even making contact with the throttle piece.

The bike never revved that high at idle before I tore in to the carbs and rebuilt them. I'll try the carb cleaner on the throttle shafts and see what happens.

Thanks for the link. Is the process to replace the mikuni seals the same as hitachi?


Thanks

 

In my inattentive state I just noticed that you have a 550. The link to the seal replacement walk through will be very similar except your Mikuni carbs have the butterfly screws that are peened over rather than locktighted in. A bit more of a PIA. Don't force them out or you will probably damage the shaft. You will need to carefully file the 'peening' (if that's a word) off. I've never done this. Perhaps someone else can offer a bit of insight.

 

Aargggg. Lol. Mikuni Can't make it too easy. Thanks man

 

I have ordered the throttle v-seals from chacal.

I figure if im now going to break the rack to replace the throttle seals, I might buy some carb dip.
Also, i've been looking at this Ultrasonic cleaner that HF sales:
http://www.harborfreight.com/25-liter-ultrasonic-cleaner-95563.html#pr-header-95563.
Anyone use this before? Is it worth it? Reviews seems positive.

I figure a nice dip and then some ultrasonic cleaning might shine the carbs up a bit.

I have also ordered larger main jets and pilot jets to see if that will improve this carb tuning thing.
stock pilot is #35 and main is 112.5. I ordered #117.5 main and #37.5 pilot.
We'll see how it goes.

 

Yeah!!!!! After breaking the rack, dipping each carb in carb dip for some time and replacing throttle shaft seals (thanks Chacal) the thing STARTSSSS!!!..

Oh and i replaced the main jet and pilot fuel jets with a bit bigger ones.

The idle is a bit wacky, but setting the choke and blipping the throttle a bit kept her running.

I know I need to do a vacuum carb sync ( need a YICS tool), and valve adjustment (dreading). Rather, i need to check/adjust valves before sync per fitz recommendations.

Anyways.. Looks like we're getting there, slowly, but surely. Thanks for everyone's help.

 

Good call on the larger jets, the pods are way less restrictive than the stock box.

These XJ's are funny when it comes to the mix. I have rebuilt 4 different carbs on 4 dif. motors and they were all WAY more forgiving than the XJ-if it isn't just right it will let you know.

Don't dread the valve adjustment it is seriously easy when compared with the carbs IMHO. Although I had a sticky shim and it took a while, after doing it the first time I was able to do it the second time with no problem whatsoever. In fact now it seems as easy to me as an oil change. I did construct a tool to remove the shims from a computer chip puller that made it much easier the second time around.

 

Nice MercuryMan! I actually read through your thread the other day on changing the shims as i have been researching more on the topic before i dive in.

I am interested in more info on the tool you made. I have the same exact tiny screwdriver and hemostats that fitz uses in his write up. I wonder if i would be ok with just using those.

I thought I was in the clear with my carbs. It seems that on a cold start, it will refuse to start completely. I found that I have to remove a pod on carb #4 and hold my hand over it, the bike will start up fine.

Any ideas on how I could avoid having to do this? Should I increase my pilot or main jets even more? Maybe put socks over my pods to restrict air? Anyone have ideas?

Thanks! Take it easy!

 

Are you dedicated to running pods, or did they come on the bike? If you want to make it really easy on yourself, find a stock airbox.

To even HOPE to get it to run with pods, you'll need to get those valves in spec, and get the carbs as 100% as you can get them beforehand. When you put your hand over one of the carb throats, you're creating a "real" choke (as opposed to the enrichment circuits.) The float levels are going to need to be right on, the carbs dentally clean, and very carefully bench-sync'ed before it's going to want to run.

As for your jet selection, did you talk to Len, or read his recommendations? Based on his chart, I'd be looking at going up FOUR sizes on the mains, and one on the pilots; for your configuration (pods with the stock exhaust.)

But it's not going to run if the floats aren't accurately set, the valves in spec, and the carbs carefully bench-sync'ed first.

 

Not 100% dedicated. When i got the bike, it didnt have any filtration media(airbox. pods.. nothing.)

My frame was modified by PO. Would a stock airbox fit in this modified frame setup?

its next on the list.

I can say without any uncertainty that i have been in these carbs more than you have fingers and that each time i have cleaned or sprayed or replaced something.

I know previously that i had some doubt and would suspect remnants of dirt or something in the carbs. I know for a fact these carbs are golden as of yesterday. I have dry-set floats to 21.5mm (BS28) and validated that my wet-set within the 2mm+/- fuel height as per my Clymer manual. The only way they'd be off is if my harbor freight digital caliper had been off. (well... it is harbor freight afterall)

I have bench sync'd. I performed this by equally lining up 1 2, then 3 and 4 thrpttle plates to the 2nd hole (pilot) in the neck. then balanced the pairs so they open equally

I did not talk to Len, but did see the formula and examples.
stock i have #112.5 and #35. I upped to #117.5 and #37.5 and IIRC, those were the next steps up which would be a difference of FIVE and 2.5 on main and pilot jets. Wouldnt it run richer from that? Perhaps the valves are out of spec causing weirdness.

Those valves again. Carbs i believe to be tip-top at this point after the hours and money i have put into them.

I thank you for your comments, suggestions, information, Fitz. I've read through quite a few posts where people have had probs and you reiterate your thoughts and ideas over and over and they cant figure out why it doesnt work until they perform just what you've suggested to the "T", then ba-da-bing.

Thanks again.

 

Pretty sure a stock air box is out of the question. The frame is not going to let that happen.
There is a guy who is running pods on a 550 and it sounds like he has it running pretty well. Look for the video on you tube of 550 XJ

 

I still need to check my valves....BUT
I found I can cold start now - it will idle 1100-1200 RPM.. havent ridden yet since i need a seat, (any great DIY seat pan ideas?) this is AWESOME......

did i mention that, i need to check my valves. Maybe today after work.

 

As far as a seat goes you could try and find an old tractor seat or pick this up and make mounting brackets for it
http://www.ksl.com/index.php?nid=218&ad ... earch=seat

 

good find!! i just saw your post just now and sent the seller a text and he just sold it.. ah well..

thanks man