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Discussion Starter #1 (Edited)
Hello,

Here its me again, I found forums help really a precious thing and leart a lot from advises. Since my lasts posts where I couldnt find a solution but at least I could diagnose and verify my check lists of possible problems.

To resume... warning, its a long story:

1) about three years ago :rolleyes: I decided to take the engine out for maintenance... let me bold this: it was one of the worst decisions I made the bike was fine for its age, so I let my trusty mechanic friend did the work. In my country we couldnt get new cylinder kit so he could only change rings and polish to the cylinders (dont know how to explain myself here :unsure:, I mean cylinder maintenance when you take them to a special shop that polish or scrub them). Unfortunatelly, there where no new original rings kit, so my mechanic told me he got new Susuki 1100 (as far I remember) rings that are "equal"


2) we ensambled the engine again... after almost a year. And the problems started... first the bike had some rattling "fast little push backs" in its riding when you were between 4000/4500 rpm and speed up fast (I mean with rattling like if you are in 5th gear running about 40kph and there you just speed up hard... the bike tends to shake :unsure: push back, thats normal but in my case I ride in the right gear). Well the push backs where produced about that rpms very very fast and then it runs just fine.

3) my mechanic told "its nothing" that the rings and the work done will adapt/accommodate with after some kilometers and oil change (that will clean any waste)

4) I ride it about 500km trying not to demand it too much, then other 500km running faster. Here I realized one more thing... before the engine work, I remember running on a highway parallel with a friend in a car and it reached about 175kph (winds favours me I think :) . Well, this time I think I did not passed 140kph, even I have about 15% extra throttle to give, that %15 seemed not to accellerate a thing (throttle cable is ok and moves from max/min as it should, tested)

5) after that, the rattling continued so I told my mechanic... he noticed the problem too and told me it might be a problem in the carburator. So, I got a rebuild kit, change rubber diaphragms, floats (one was punctured), also the for rubber tubes that connects the carb between engine and air filter frame... recalibrate everything... and nothing, the problem remains. Here I got some hints from other local mechanic, told "take out the carb air cut off valve, and block the carb outputs", that was easy so I tried, it run really bad, you had to play a lot with throttle and clutch to start running, so... damn philosopher mechanic

6) the next step was "hey the hydraulic tappets where kind of old", ok... I got 6 original new ones, hard to get, lets take out the engine again, its easy :p and effort-less, we did it again and changed the hyraulic tappets. I have the repair/maintenance manual so my mechanic followed the indications to install them and insert the right shims (I think)

7) started the engine again! excellent, at least it start :), test it... the rattling changed a little, now it occurs between about 2500-3000.

8) I got out of peace of mind fuel so I let the bike to rest about a month, recentrly I started it up again... and damn! now it only starts in front cylinder with choke on, rear cylinder starts about 1 second and then dead, only front cyl on. Rear cylinder wont start, if you accelerate the bike it just stops. If I turn off the choke, bike goes off too.

I thought it was water or condensation so I purge both carbs with the purge screw to leak the fuel. Then, I feel again both carbs (joining Bl/Y and Bl cables from fuel pump so it start filling carb until floats cut. Purge again... I blow some air with an air compressor trying to "clean" if there is something stucked, my mechanic recommend me to blew some air into the mixture screw (taking out the mixture screw first) and also into the purge screw (taking it out first) but nothing changed. Also I check the carb diaphragm from the rear cylinder, its fine, moves without a problem.

I think the only option is taking the carb out again and really inspect the conducts for any stucked dirt that might have passed the fuel filter, but the carb was really cleaned, the filter is new.

So I am afraid now its the rear cylinder rings that went wrong or dont know :-(

Thanks for reading and hope you can give me any clue! I need a X-Files Molder/Scully team to figure out this.

Thanks again,

EDIT1: Also have checked sparks, and changed front sparks to rear sparks, same problem.
Checked magnets gaps (those inside the right side crankcase)
Checked ignition coils (with a tester as showed in manual, they are between the correct values)
 

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You are sure learning a lot about your bike, but the hard way. A compression test will tell a lot about the health of the cylinders. Do it with throttle open. It should get up to 180+ pounds or=Metric
The carb usually won't make a dead cylinder unless it is dry.
When cranking and the rear cylinder is dead, spray some carb cleaner in that carb to see if it starts running.
 

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Discussion Starter #3 (Edited)
You are sure learning a lot about your bike, but the hard way. A compression test will tell a lot about the health of the cylinders. Do it with throttle open. It should get up to 180+ pounds or=Metric
The carb usually won't make a dead cylinder unless it is dry.
When cranking and the rear cylinder is dead, spray some carb cleaner in that carb to see if it starts running.
Thanks Swifty (you give me help before (y)), yup... I am learning, thats the only thing that keeps me trying. I did a compression test in the past, with a tool like a spark but just rubber that I had to push into the spark hole (kind of not optimum but helped) that time the compression gave about 175/183... that means more near the lower limit. I will test again! hopefully (well not hopefully) the problem is a bad ring, bad compression and if thats the case I will be happy knowing what to fix!

Surely the carb is not the problem, the cylinder and spark shows too much fuel (as the only way to start it is with full choke) so fuel goes to the cylinder :rolleyes:

Yesterday I take out the carb diaphragm from the rear cylinder (the one with problem) at least to see if the rubber was out or something stucked... but not, it was ok. One strange thing more, is the plastic part piston (we call it here "courtain") and inside it seems to have some oil and fuel... little. Will upload a video later.

Thanks,

Here the video: https://photos.app.goo.gl/fuhFnW3cK9gUHs6s9
(sorry I am talking in spanish sending it to my mecanich, and also cursing a little :giggle:)
 

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The wet liquid on the Slide body (courtain ) Looks like too much fuel which may be normal trying to start it with choke and not firing on that cylinder.
Or it shows it is flooding that cylinder and the plugs can't fire being flooded.
Don't worry too much about the exact compression. The best compression is with a warm engine so even if you have 160-170 # that will run OK.
Have you seen spark on the rear cylinder?
 

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Discussion Starter #5
The wet liquid on the Slide body (courtain ) Looks like too much fuel which may be normal trying to start it with choke and not firing on that cylinder.
Or it shows it is flooding that cylinder and the plugs can't fire being flooded.
Don't worry too much about the exact compression. The best compression is with a warm engine so even if you have 160-170 # that will run OK.
Have you seen spark on the rear cylinder?
OK, wont worry too much, but will re-test just in case it has gone really low (since last measure when it had just the rattling problem) and post back.

Spark, yes! spark from both sparks are ok... did test it taking little out the cap you hear the spark, algo taking the spark completely out and putting it near the exaust so the sparks shows, and yes... it shows!). Also, just in case I took front sparks and moved them back... and like nothing, back cylinder wont start.
(time ago I test the coils, the omhs where just fine as manual tell, but havent test them again)

(thanks again for your guide Swifty)
 

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Discussion Starter #6
Well... found the problem!

I took out the carbs... the slow running jet from the cylinder that wont start good was almos closed by a dirt. And the problem might be my fault. I have new fuel filter anyway, but... as latest works done to the bike I had to take the upper tank several times (I was really carefull) but mechanics just use tongs and force no patience and the rubber tube from upper tank to lower got a little crack and leak. So couldn find any similar curved tube oem... so I got a "water" tube (car part) that fits just fine... but... seems the kind of rubber and fuel start to react and some builts small particled that pass the fuel filter and ends stucked where the hurts enough.

So... its running again, will go out today and test the rattling and hope that Easy Rider God helps :p
 
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