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My points are OEM.

ok Ill start referring to manual and just ask more questions! Im glad I found this sight becuase I wouldnt know enough to question common motor.
With my carbs being set a 23mm, or the floats too high in general, can it cause hydro lock?
No to the hydro lock. These carbs have overflow tubes. Hydro lock usually occurs with bikes that have no overflow tubes and usually vacuum operated fuel valves that fail in the open position. The cylinder must be almost full or partially full of fuel on the compression stroke when starting is attempted for hydro lock to occur. Nasty damage happens after that.

You may want to do a search for other vintage honda sites......some have very good resource libraries ...
 

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Discussion Starter #182
Quick update, I did another test and I got the bike was doing same thing, loses power at 6K rpm. So I reached down and put the choke on and it kicked up to redline.
So thinking, with it working better with choke on, does this mean I have an air leak or a fueling issue? I did use (you guessed it) common motors carb kit. I plant to order oem and used parts to replace mine if I cant find them.

I rode a bit with choke on and wow, what a fun little bike. is it hard it on to ride with choke on?
 

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Discussion Starter #183
2nd question, could said "air leak" come from piston rings or head gasket?
 

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Not good to ride with choke on. The spring loaded panel on the choke plate could break off.

Needing choke indicates either an air leak or fuel problem. Fuel level too low in float bowl etc.
 

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Discussion Starter #185
Not good to ride with choke on. The spring loaded panel on the choke plate could break off.

Needing choke indicates either an air leak or fuel problem. Fuel level too low in float bowl etc.
Thanks for that heads up. If you give me a starting place, with choke off, when I get to 6k rpm if I try to force it with more throttle it actually bogs down further. Then it is like it loses power and the rpms drop off, and its like it is out of gas, letting off throttle and down shifting a for a bit then will bring it back to life. Does this sound like a fuel bowl issue? The drain plugs do have a slight weeping leaks I need to find some gaskets.

Good news, I found 1 set of my original carb parts. I have the others I am certain in another container. So I plan to convert back to my OEM stuff in terms of the jets and needles. However I cannot use the fuel bowl valve as I killed it getting it out with pliers :(
 

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Discussion Starter #186
Spent time today with an unlit propane torch trying to find an air leak. RPMS do change when I feed it into the stock airbox, but puttint it all around the carbs and head gasket not getting any reaction.
I do hear a valve clanking going to re adjust again.

If that doesnt do it, then I think the cheap kit I put into the bike is crap. I also have not done much with the mixture screws (1 turn out) but i doubt they can affect it enough to fix this. You agree?
 

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Floats too high gives a low fuel level. Hydrolock would mean you have a load of fuel in combustion chamber and also fuel in oil as it will be draining past rings when standing. It's highly unlikely, usually caused by getting water into engine as you need a 'lot' suddenly, normal fuel 'drip' would be too slow.
Remove dipstick and smell oil, it's pretty obvious if fuel is mixed in and oil level has gone up
 
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Discussion Starter #188
Floats too high gives a low fuel level. Hydrolock would mean you have a load of fuel in combustion chamber and also fuel in oil as it will be draining past rings when standing. It's highly unlikely, usually caused by getting water into engine as you need a 'lot' suddenly, normal fuel 'drip' would be too slow.
Remove dipstick and smell oil, it's pretty obvious if fuel is mixed in and oil level has gone up
I did check that out in the oil. No issues there. My floats are at 24mm but measured at 90 degrees, so the high vs low thing gets confusing. I assume the way I set my floats my bowls are overfilling as is evident when on the side stand there is some leakage out the drain plug and out the overflow.

Ill check again for air leaks but I think the carb kit form common motor is jetting incorrectly. Once it warms up again Ill install my stock jets.

I had an old xj600 with down draft carbs and no overflow. The petcock failed it caused hydrolock as my float valve was leaking. This was after sitting a few days. Destroyed the motor completely when I tried to start it.
 

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Yep, it's counter intuitive but when carbs are fitted the higher the float, the 'lower' it actually is 'right way up' so fuel level is low.
Did you oil or grease the o-rings on new shut off valves?
If you didn't, there is a good chance they got damaged when fitting. (it's a good idea to oil any o-ring or seal when replacing stuff)
If housing is clean, a drop of oil will allow new parts to slide in with normal thumb pressure, if they don't slide in easy, something is wrong.
You probably know I do a lot of CB360 and CB350 carbs so I've seen a lot of badly done 're-builds', some of the worst have been from 'professional shops' who were trying to maximise profits by cutting corners which only works short term then causes a ton of problems later on.
Realistically, that's a part of the reason I have issues with CMC video's.
You will be much better off learning how to do stuff properly, FSM and advice from here will give you a miuch better result eventually and is still, way cheaper than going to MMI or Wyotech
 

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BTW, I was shop manager in a Suzuki/Yamaha dealer when XJ600 was launched.
Our parts guy loved it much the 'demonstrator' became his personal transport for a year an it never had a 'test ride' by anyone (including me)
I'm still in touch with Dave on Facebook although he's been retired quite a while now
 

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Discussion Starter #191
So I used "marvel mystery oil" on the gaskets and orings. It causes them to swell and get way soggy.
So I have a set of OEM rubbers. I also ordered 2 carb kits that arrive today from 4into1. I also found 1 carb worth of my oem jets.
Im looking for the other set.

The set from common motor, when Iook into the emulsion tube where they drilled holes, there is metal on the other side of the hole as if they used a super dull drill bit. (as if the pocked the holes in there)

Ill also use a bigger jet that what is in there now.

PS. Xj600 was a 1994. my 2017 R3 has more power. SO I dont miss it. That bike sucked all around. Not to mention it needed choke for 20 minutes to warm up even if it were 105 degrees out. Yes, that was by design too. Emissions.
 

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Are you in California?
We got a lot of 'grey imports' and used bikes from Cali. Always had to re-jet to European spec to make them run properly in Britain
 

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Discussion Starter #193
So I bought some new kits from 4-into-1 and compared them to the "oem" stuff I took out of my carbs. I have no idea if my carb parts are OEM or not but the 4into1 kit looks identical.
Installed it, I used the 70 and 110 jets. I reset my floats to 25.5 mm holding at an angle.
Bike started right up, but having nearly the same issue, cant get over 6k rpm. However with choke off I can get it up to 7k if I let it build up to it. Now however, with choke on the nearly dies after warmed up. Ive been messing with the mixture screws though.

Im going to check again for leaks, check valves again etc.

Im at a loss, did I botch installing the new rings?
 

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OEM pilot jets have a 0.80mm cross drilling. Every 'new' jet I've looked at has a 0.60mm cross drilling.
Most of the other parts seem to meet OEM spec though.
You do have the rubber plug on top of pilot jet opening? It needs to feed from primary main jet only or bike runs rich
 

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Discussion Starter #195
Yes I always use the plug. I realized I may have adjusted the valves incorrectly. What I do is go 90 degrees past LT on the compression stroke and ensure none of the tappets have any pressure on them. Then I adjust both sides. Sounds like I should be doing it on LT and T on compression? Would that matter? I do hear a valve clanking anyways so Ill check.

I compared the holes, they do look the same to the eye. I dont have anything to measure them with.
 

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I've seen just about every 'shortcut' you can think of (and many I didn't think possible).
None of them work reliably.
Do adjustment at TDC, the opening and closing ramps will give a false reading at any other position.
Simplest thing to do is turn motor slowly counter clock (normal rotation) and watch intake tappet. It goes down and then up before TDCC.
I use a 14mm on generator rotor bolt jammed against footrest to hold motor in position as the springs on 'the other cylinder' try to turn motor past TDCC
You can't do both sides at one setting? (or did you mean intake and exhaust on one side?)
 

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Discussion Starter #197
No I did left and right at that setting. (90 degrees past LT)
I did check slide function by blowing into the carb intake with my mouth, they did open up all the way. i did not however use sealant on m diaphrams, should I try that as well?
Ill do a proper adjustment on valves but I highly doubt that will fix it the issue.
 

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I read that in a Honda shop manual once, 90 degrees past LT is where all four cam followers are the base circle(valves closed), you can adjust all the valves at once/adjust the cam chain too. That's also the best position to store an engine, all four valves closed so moisture can't enter the cylinder.
 

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Do a voltage check at the coils with the engine running. The voltage should be very close to battery voltage. If it isn't then check the ignition switch connection, kill switch (often the culprit in voltage drops) and connections inside the headlight bucket. I chased a similar problem that ended up with all three plus a partially broken wire from the headlight bucket to the coils.
 

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Screaming Tiger, I have a quick question for you, my motor is out for teardown and parts checking and I'm about to learn what gasket kit and parts/rework I need. 21k OEM miles.

What gasket kit / headgasket did you use? Did you like them?

I'm looking at the 4into1 set right now as they have a series of kits, one including pistons and rings (0.25mm over)
 
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