Don’t like the bend in the tip of the mixture screw. Hopefully it wasn’t tightened enough to damage the seat in the carb. I’d find the “correct” screws and try adjusting the carbs. Maybe no damage has been done.
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Van Islander's TX650A - Quest for a Daily Rider
- Thread starter TX650A Van Islander
- Start date
It's a project that I'm working on that goes back to XS1 - I just included the year range in question and that's where the transition began of US being different (AFAIK). The Z-8 # 341-14941-84 (used on 447 carbs), the Z-6 # 341-14941-86 (used on 306 carbs).
The US carbs (584) for '76 (C) go to a Z-2 with p/n 341-14941-88. I do show '77 non-US carbs transitioning to 584 series that began on US models in '76. Some of the websites, apparently, use your IP address and it's difficult to find applications for different locations. Some of my references are translated from German. The point is: one has to examine several parts of the carb to verify what was originally shipped from Japan and the style part intended as a replacement. In this case, a 256 pilot screw where a 584 was expected - the 256 could be correct if the carbs are 447
I ditched that screw with the bent tip when I realized it was damaged. That's when I realized they are likely incorrect. Its difficult to see the seat way down in there. It seems there is a mark off-centre at the seat; hopefully it will work ok.
Thanks for the feedback. More detail to follow.
Thanks for the feedback. More detail to follow.
Unless the seat is completely buggered I think you'll be OK. If you think about it, it's just a simple needle valve. If it was a valve that needs to be completely closed.... seated (like the float valve), yeah... that would be a problem.
But this particular application has the needle valve unseated during normal operation. Once you screw it out off the seat, you're just regulating flow. And you should be able to compensate for a slightly buggered seat as you adjust it for a smooth idle.
But this particular application has the needle valve unseated during normal operation. Once you screw it out off the seat, you're just regulating flow. And you should be able to compensate for a slightly buggered seat as you adjust it for a smooth idle.
Yeah, I can't see shit to begin with. It's surprising the images a phone camera with flash will sometimes yield - may be worth a try: not just to examine damage, but it may give a clue of what the correct screw is.
Jp, the needle jet part numbers in your chart are correct but you have them labeled wrong. The "-84" is not a Z-8, it's a Z-6, and the "-88" is not a Z-2, it's a Z-8. Also, all the Z-2 listings I've seen start with "2F0", not "341" .....
Thanks - I'm still work'in on it as time allows... I'll make those corrections. The original write-up was in German that I found somewhere (forget right-off) and thus far I've run the part numbers through cmsnl.com and crossed to Niche, yet to go back through and reference a second source. I now see were partzilla gives Mikuni designation (Z8,etc) along with p/n - that'll help straighten me out (cms didn't)
I'd be happy to share the raw spreadsheet with you, or anyone, that would like to add or edit info.
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Time for an update. I found the 24mm seals which Jim recommended. Lucked out and got them from a local industrial supplier. I still haven't got the proper adjustment screws I need; they don't seem to be available through any Canadian supplier at the moment and I've been unsuccessful finding the Mikuni part number so I could perhaps order them locally. Will likely have to order through US supplier and pay a lot more by the time they get here. No rush though because my fall riding season came to an abrupt end on Sunday afternoon.
I lowsided my DR650 on pavement at about 30 to 40 kph, and broke my right ankle on impact. Pretty intense feeling as it happened. I figured I broke it. Lying on the road looking at your running bike lying there 15 feet away, leaking gas out of it, is a lousy feeling. After some reflection on how my own stupidity and complacency and over confidence caused this single vehicle accident, I picked the bike up and rode it about 25 km home. By Monday am I had an air cast and some time in the next few days I'll have surgery to ensure it doesn't heal incorrectly.
I saw a thread earlier today about some poor guy who advocated no helmets and ironically was killed not wearing one. We have to wear them here in BC. I've never not worn one. Luckily for me I was wearing my full Revit gear, good gloves, full face, and my Sidi adventure boots. I'd been riding on dirt roads and scrabbly single track rocky trail earlier in the day and like to be prepared. Proper riding gear matters. But I'm as guilty as the next guy of riding my TX650A with jeans and t -shirt and gloves on a hot summer day.
My message here to my on-line XS-650 friends is let's not be complacent. I'm 57 and have about 30 years of riding experience starting at 19. ( a few crazy years without bikes) I figure I'm a good rider and its not going to happen to me. We can all let our guard down too much at times.
I lowsided my DR650 on pavement at about 30 to 40 kph, and broke my right ankle on impact. Pretty intense feeling as it happened. I figured I broke it. Lying on the road looking at your running bike lying there 15 feet away, leaking gas out of it, is a lousy feeling. After some reflection on how my own stupidity and complacency and over confidence caused this single vehicle accident, I picked the bike up and rode it about 25 km home. By Monday am I had an air cast and some time in the next few days I'll have surgery to ensure it doesn't heal incorrectly.
I saw a thread earlier today about some poor guy who advocated no helmets and ironically was killed not wearing one. We have to wear them here in BC. I've never not worn one. Luckily for me I was wearing my full Revit gear, good gloves, full face, and my Sidi adventure boots. I'd been riding on dirt roads and scrabbly single track rocky trail earlier in the day and like to be prepared. Proper riding gear matters. But I'm as guilty as the next guy of riding my TX650A with jeans and t -shirt and gloves on a hot summer day.
My message here to my on-line XS-650 friends is let's not be complacent. I'm 57 and have about 30 years of riding experience starting at 19. ( a few crazy years without bikes) I figure I'm a good rider and its not going to happen to me. We can all let our guard down too much at times.
Well that sucks. Hope it heals good for you.
Holy crap! I’m sorry to hear about your accident, it sounds like you are wearing top notch gear too. I’m really surprised to hear about your broken ankle, those boots have got to be pretty solid construction.
Although weird things do happen, there are a heck of a lot of bones in your feet. Hell, I broke my foot at work just from pushing a heavy container across a smooth and level cement floor.
Holy crap indeed! Hope you heal up quickly and well. The more I read about other's misfortunes, the more I see that I need to gear up. Late yesterday, I ran through a flock of wild turkeys on one of my downhill runs... in a corner, leaning heavily (at least for me!). Missed them, but the one closest to me couldn't have been more than 12" from my front wheel as I went by. That would not have ended well, had there been impact!
So sorry to hear of your misfortune. Hopefully you’ll be on the mend quickly. It‘s good you were wearing the proper equipment and apparel, otherwise your injury may have been worse. Thanks for posting this… maybe a wake up call for many of us. Get well soon!
What a sh*t trip for you Van; I too hope you heal well and fast (but dont force it let it heal).
Agree with your sentiment about riding gear. I too have had a few 'Offs' and my gear always saved my skin. I always wear Helmet, amoured Jacket, Gloves armoured pants (whether denim, leather or Tech fabric), and of course appropriate bike boots. There is no excuse today as any style / fabric / leather etc is available; modern materials allow a cool look whatever you style choice be it Mod / Rocker or just Cruiser. Yes they are a bit more expensive than regular Jeans & T shirt; but what price do you put on your life & limbs?
Happy New Year gents! I'm walking around, almost no limp, and will continue to regain flexibility as I keep stretching and walking. Finally I get to be back in the shop putting the TX back together! I ended up buying the proper '76/'77 mixing screws from Niche Cycle. I installed one today but the odd thing is when they are turned out from fully seated by 1.5 turns as per the carb guide, they are quite loose, and will surely vibrate out. Ideas? The new screws are pictured next to one of the incorrect ones, which was similarly loose when backed out 1.5 turns.
Good to have you back @TX650A Van Islander
Looking forward to your further instalments
Looking forward to your further instalments
Good question but they do have 4M1 needles and Z-8 needle jets, so presumably correct. I installed #125.0 main jets and #25.0 pilot jets, at least for now.
Glad to hear you’re back on two feet again! I’m sure the experts here will be able to help you with your carb questions.
Here's a pic of a '76-'77 mix screw set at 1.5 turns out. Pretty much all the threads are in the carb body and only that step between them and the knurled head shows .....
Is this how far out your screws are? Here's a shot of an original screw and spring. Looks pretty much the same as your replacements .....
Is this how far out your screws are? Here's a shot of an original screw and spring. Looks pretty much the same as your replacements .....
