Instant red lining in neutral

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hondaror
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Joined: Mon Mar 03, 2014 8:44 pm
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Re: Instant red lining in neutral

#46 Post by hondaror » Tue Jul 19, 2016 11:23 pm

That's just mechanical sync. Buy a Uni Syn. Really tune the bike.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

LC Cnd
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Location: Vancouver Is. Canada

Re: Instant red lining in neutral

#47 Post by LC Cnd » Wed Jul 20, 2016 2:50 am

B4 I buy a uni-sync, I going 2 have to invest in a new set of rubber tipped needle valves it appears. Turned on the fuel and watched the right carb's overflow tube gush gas onto the driveway. Disappointing. Removed the carb and ck'd the float and it was properly leveled and the spring had recoil. The left carb is all right - no leakage and the bowl was full of fuel when I drained it.

Bare
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Location: vancouver

Re: Instant red lining in neutral

#48 Post by Bare » Wed Jul 20, 2016 1:59 pm

One can diy a Carb sync contraption from a few bits of Clear tubing.
Every bit , if not more, accurate. Google for How to.
Fresh 'decent' float valves are a basic must have.
One CAN rehab old ones though :-)
Find a wee ball bearing that fits into the Float valve body Then tap the ball with a drift a couple of times.
That reforms the brass hole into a valve shaped uniformity allowing the pointy needle to seat effectively.
Yess it works. Very well actually and repeatedly.. as long as the pointy bit isn't grooved.

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2smoke
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Re: Instant red lining in neutral

#49 Post by 2smoke » Wed Jul 20, 2016 8:46 pm

Sometimes to get the valve to seat and stop the leaking fuel you can just tap the float bowl with a plastic screwdriver handle or roll the bike forward and backwards and hit the front brakes hard to "slosh and shock" Lol.
Colin
79 RD400F Daytona Special
81 RD350LC
89 TDR250
75 Kawasaki H1 500
77 Can-am Tnt250

LC Cnd
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Joined: Sat Feb 08, 2014 5:39 pm
Location: Vancouver Is. Canada

Re: Instant red lining in neutral

#50 Post by LC Cnd » Wed Jul 20, 2016 8:50 pm

The DIY carb sync idea is attractive (reviewed vids). How to create a seal, for vacuum on the carb, is the challange. Large rubber stopper? The tapping idea a nice tip. I also found the rubber retaining gasket ring, inside and at the base of the needle valve assembly, a bit dried out - $4 replacement. Oddly, that ring is not featured in the RD parts catalouge carb exploded diagrams (B10 & 11). Perhaps it's because I have the British version. Will see how this all works out tonight.
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hondaror
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Location: Alberta, Canada

Re: Instant red lining in neutral

#51 Post by hondaror » Wed Jul 20, 2016 9:48 pm

Always bench test the carbs with fuel...and yes, shock is often effective. Buy a Uni-Syn. Am I repeating myself?! For damned good reason.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

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2smoke
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Re: Instant red lining in neutral

#52 Post by 2smoke » Wed Jul 20, 2016 10:53 pm

Hey is that float bowl gasket in the picture on backwards or is it multi use
Colin
79 RD400F Daytona Special
81 RD350LC
89 TDR250
75 Kawasaki H1 500
77 Can-am Tnt250

LC Cnd
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Location: Vancouver Is. Canada

Re: Instant red lining in neutral

#53 Post by LC Cnd » Thu Jul 21, 2016 2:22 am

Yep, it repitition & appreciate the suggestion. Cuze this project is on a budget now, it's on the wanna list - tuitions are cheap anymore. And yes, the float pin is secure.

Update the over flow leak stopped (good) after the fuel lines filled. Tried to fire her up - nothing. Ck'd the plugs: one wet; the other dry. I'm going to walk away from the bike 4 a bit b4 I break something.
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LC Cnd
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Re: Instant red lining in neutral

#54 Post by LC Cnd » Fri Aug 05, 2016 6:35 pm

So, pulled the carbs apart (again). Tested the floats to see either would sink- neither did. Used a micrometer to set the float level proper according to the shop manual. Used tooth paste as compound to seat the float needles (finest I could think of). Hooked up unused fuel line to complete a leak test by attempting to suck air passed them - both sealed nicely after cleaning them up. Did stick a needle thru the bowl drain holes and took out some debris and blew them clear. Re assembeld the carbs. Still getting weeping on the right carb while parked on the center stand in the garage. Weather been 30 + Celsius so popped off the gas cap to releieve any possible pressure - still dribbling. All I can think of is the float must be still high or something else. At a lost here or is normal dripping due to temp increase?

Bare
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Re: Instant red lining in neutral

#55 Post by Bare » Fri Aug 05, 2016 11:52 pm

Sucking isn't a good test of the float (needle) valve
Attach a fuel line to the carb inlet.
Hold the carb upside down so the weight of the Float is holding the needle valve closed, then: ...Blow... through the fuel line.
Shouldn't leak at all.. and if it does?
Either try again with reseating (do the ball bearing /hammer trick to reform the valve seat)
OR buy decent quality New float valves

hondaror
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Location: Alberta, Canada

Re: Instant red lining in neutral

#56 Post by hondaror » Sat Aug 06, 2016 7:29 pm

What kind of K's on the bike? Seat needles may be worn out and should be replaced. Don't dick around with trying to fix them. If high K's.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

LC Cnd
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Posts: 1454
Joined: Sat Feb 08, 2014 5:39 pm
Location: Vancouver Is. Canada

Re: Instant red lining in neutral

#57 Post by LC Cnd » Sun Aug 07, 2016 11:45 am

36524 km's. Suspect that reasonable - assuming that the carbs on it are original. Note I can buy new float seats fm Yambits but the needles are metal tipped. Prefer the rubber tipped one's - OEM?

Bare
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Location: vancouver

Re: Instant red lining in neutral

#58 Post by Bare » Sun Aug 07, 2016 3:16 pm

awww fff's
Do, the ball bearing in the needle valve seat repair.
It's a Proven moto mechanic's 'trick'.
It works.. Period. Takes all of 1 minute to do.
Rubber tipped needles are.. Unless visibly damaged ?.. V long lived.
Going to be rain season again.. in a few weeks.
Snooze and lose :-)
PS: By my observation virtually ALL 'old' bikes show ~35,000 K's on the odo.
Clearly that's what Odo resetter's all think is a palatable number... to fool buyers.

LC Cnd
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Re: Instant red lining in neutral

#59 Post by LC Cnd » Sun Aug 07, 2016 9:53 pm

Time to get my hands dirty. I'll complete a proper leak down test n' see how that works. If that fails, I'm in search of a ball bearing that matches the float needle width and give it a shot (Scottish frugality kicking in here). If that fails - new needles it is Rory b4 the riding season ends hopefully. It's raining today so good timing.

LC Cnd
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Posts: 1454
Joined: Sat Feb 08, 2014 5:39 pm
Location: Vancouver Is. Canada

Re: Instant red lining in neutral

#60 Post by LC Cnd » Mon Aug 08, 2016 10:56 pm

YFZ350 Banshee1988 the same carbs as a Elsie - they appear to be.

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