Start issue, high compression.

[arendal]

Hi.

I just bought an old fj 1100. But it has a cold start issue. When hot it runs and start fine, maybe some rattle from clutch.

I tried sync carb and adjusted mixture screws 2 rounds out. I tried fine adjust mixture screws, but they don't affect the idle speed.

I tried a compression test, but i think its very high. About 13 bar(188psi) on all cylinders. I think i should been 9,5 ?

Could my problem be valve clearance?

Hope for some good ideas.

[oldktmdude]

   Valve clearances will not give you high compression, lack of clearance will give you the opposite. I suspect you may have an engine with a Wiseco kit in it.
I have a 1219cc kit in mine, my compression runs between 180 and 190 psi. Your choke circuit may have some blockage causing hard cold starting. Look there before anywhere else. Your battery may also be down on power for cold cranking. This robs voltage from the ignition system (coils) and makes cold starting harder.   
Let us know how you get on.
   Regards, Pete.

[arendal]

Hi Pete.

Thank for your answer. Is there anyway to see if wiseco kit is mounted?

I sure noticed that starter will rob the voltage from ignition. After tried starting over a period, i dont have change to start it, before recharge.
Battery and plugs is new. Carbs should be rebuild (By previous owner).

This morning it startet right away with full choke. I gave it a little throttle, and let it idle for a half minute about 2000rpm(Running rough).
Then i turned a little bit choke off, still holding the throttle, and the engine died right away. And then it could not start again. With full choke and no throttle i could get i popping and nothing more. As soon i touch throttle or choke it stop popping. 
So i gave up... 

I can hear starter go a little bit slower if i activate throttle or choke while turning.

[red]

This morning it startet right away with full choke. I gave it a little throttle, and let it idle for a half minute about 2000rpm(Running rough).  Then i turned a little bit choke off, still holding the throttle, and the engine died right away. And then it could not start again. With full choke and no throttle i could get i popping and nothing more. As soon i touch throttle or choke it stop popping.  So i gave up... 
I can hear starter go a little bit slower if i activate throttle or choke while turning.

arendal,

Before I would do much more, I would run a can of SeaFoam (or other good carb cleaner) through the tank, mixed as directed.  It needs a day or three to do its' magic, so hang tough.

There is a four-brush starter motor, which is a good call for the high compression.  If you have the old two-brush motor, RPM has the four-brush starter for you.

Good luck.
.

[arendal]

Hi. We don't have SeaFoam in Denmark, do you know another good brand? Lindeman Maybe?

[Pat Conlon]

Idle circuit plugged, pilots plugged. Cleaner as a fuel additive may help, may not. Personally, I would not get your hopes up.

Carb disassembly and cleaning will definitely help.

[arendal]

I noticed an leak in my CDI, plugged vacuum hose and recharge the battery. And this morning it startet and rode perfect. Rough idle when choke was on, but clean an nice when off. Maybe it solved my problem.

Is power loss the only thing that happens when vacuum to CDI is not connected? Is it possible to rebuild the CDI?

[oldktmdude]

   You will not lose any performance with the vacuum advance disconnected. It is only there as an emission control for
un-burnt fuel when you back off the throttle.
  Regards, Pete.

[arendal]

Hi oldktmdude.

What octane are you using? I think i have some engine knocking.

[oldktmdude]

   I always run the highest available. In Australia that is 98 unless you put the ethanol shit in, which I won't. If your bike is knocking, that is another good indication that you have a higher than standard compression ratio.
   Regards, Pete.

[wainot-Phil]

Your Carbs are still not clean. You have blocked passages through out you Carbs. You stated that your mixture screws do not affect the idle .that is not possible if your Carbs are spotlessy clean. I had the same problem once.Your mixture Screws MUST affect the idle .otherwise you have a blockage .. (just my 2  ents worth)

[Pat Conlon]

Listen to Phil^^^

Plugged carbies means you are not getting fuel flow (i.e. lean) so...of course you're hearing knock.

[arendal]

Hi Pete.
Yesterday i test my compression tester with a pump. Så i now know that i have high compression. A Day in future i will try pour fuel into one cylinder and measure how many ccm it contain. I can't find other way to test if bigbore mounted, beside measure cylindre.

Phil - i try some carb cleaner, if that don't work i will clean by hand.

Pat - i dont think it sound like lean. Im pretty sure it's running rich. But I will try clean.

What concern me more, is a heavy metallic rattle when accelerate reach high rpm. Sound like a loose backet, but I can't see nothing loose, im a little affraid it could be from inside engine.

Thank for all your inputs.

[wainot-Phil]

I think you are going about this the wrong way ,,FORGET ABOUT THE COMPRESSION,,,Don,t even worry about what compression or how big a Bore you have ,,,The Compression has got noting to do with you hard starting problem,,, The Bike will be hard to start and ""Knock and Rattle like Shit"" ,if you do not get the 4 mixture screws to work,,,,,,, Carby cleaner will do nothing to help you at all,,,, ""The Fact is"" ,,, ,If  turning your mixture screws in or out does  not make your idle drop or rise ,,YOU HAVE BLOCKED CARBY,s ,, You need to take the Carb's  off the Bike and completely strip them down,, Remove every removable part off the Carb Body's , Then run a thin wire through all passages and openings ,then wash/soak  them in Cary cleaner ,,then force Carby cleaner AND compressed Air through all passages to make sure they are 100% un-blocked and clear,,,,Once you have done this ,re-build the Carbs ,Refit the Carbs to the Bike  ,start the Bike up and """if the Mixture Screws still do not work then Remove the Carbs AND STRIP AND CLEAN AGAIN,,""""" because the Carb's are still not clean you still have a Blocked Passage,, ,,,,,,,,,,,,,,You may ask ,,,,,,,,,,,,,,,How would I know,,,,I know because the exact same thing happened to me ,,I ended up removing and pulling the Carbs down about 6 times before I freed up all Shit in the fuel passages's  and got all my mixture screws to work as they should ,,,,After  about the 6 clean ,,,I refitted the Carbs and found that
all the 4 Mixture Screws worked fine ,,So  I then set the mixtures and Balanced the Carbs , Once I had done this ,,""HOLY SHIT BATMAN"",the Bike Started Easy 1st time every time   Hot or Cold ,,The Motor's  Knocks and Rattles also disappeared and the Motor now  Starts ,Runs and sounds like a Brand new Motor ,,  When I am Riding the Bike now I am amazed at how Smooth and Strong the Motor runs ,  It is like Glass smooth at every speed ,with Power to Burn ,,,,,,,,I ride  along with a Big Smile on my Face,,,,,,Just Saying ,,,,,,

[Sparky84]

What Phil said but a little quieter

I cleaned my carbs twice, not with carb cleaner but disassembled them and did what Phil said with a set of oxy tip cleaners, it ran much better but still had a problem, running rich, fouling plugs.
Did them once more but this time got them ultrasonically cleaned, put them back in with new carb kits, o rings, gaskets the lot, Bench sync using information in the files section with the mixture screws.
Put them back on, started first up and has been great.
What's all the fuss about a big bore kit, after you get it going won't a dyno run give you an indication?

Cheers
Alan