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Discussion Starter · #1 ·
I been trying to restore this bike and now my problem is that only reach to 6000 rpm the carbs are clean but the engine gets hot in a minute or two and start normally
 

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Sensei
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Please restate the conditions or symptoms of this problem. ...
The overheating and 6000 RPM limit seem to indicate the bike is running out (low) on fuel flow and leaning out...(If I understand you correctly)... This could be an underjetted carb, blocked jets, or improper float levels, a bad petcock, mung in the tank, or even a blocked vent in the gas cap...... It could also be a timing related problem ......Please be more specific as to the problem.... We'll try to get you up and running..... Steve
 

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Discussion Starter · #3 ·
ok, I just clean the carbs and and the jets are properly clean. even if I ride independently neither of them can reach more than 6000 rpm.
acording to the timming lamp is properly adjusted the advace plate.
even that the bike works well but as it only got 6000 rpm, I can go to fast. the carbs are the original ones the ony variation is that I put sport filters instead of the original ones. the sparks, if I take it out are burning propperly. my brother says that could be the timming chain because yesterday I start to move the advance plate counterclock to the to the end and increase the rpm from 5000 to 6000.
 

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Sensei
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What is the compression reading?...
And did you check the advance mechanism?.....(Does Timing strobe show full advance by 3000 RPM?)
 

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Discussion Starter · #6 ·
I put these sport filters because I do not have the original ones. and about the timming avancer. it's works properly and it's new as the timming plate . I just bought from ebay. another thing. I do not have how to measure the compresion but the cilinders as the pistons are new, now is 0.5 from the original measure
 

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Discussion Starter · #8 ·
can it be that the timming chain could be 1 teeth or 2 advanced because as my brother says if I retard the ignition plate the bike increase the rpm. but as I retarded to the top only get from 5000 to 6000
 

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Discussion Starter · #10 ·
I am going to check it again if it is at 3000 or less I can't remember if I had to watch the two small marks without letters or the other that indicate the fire position.
as I have no clue about what is bad. the carbs aparently works fine the diapragms are new but the jets are the original ones. the fuel level is aparently ok. It doesn't show any leak from the cv and when I use it in never gets without gas.
I remember that before I change the diapragmas, the timming plate, the advance and the timming chain that the bike works just fine. with some problems but had more speed. I had to do these because the advance mechanism was destroyd but it was really in bad shape, like some holes to choose 3 diferent positions in the advance like more retarder or more advance.
 

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Sensei
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I realize that we have a language/translation difference that will somewhat confuse the issue, but we need specifics.... IF it is possible, pictures of the components may help overcome semantics differences.... SOME aftermarket timing plates and point sets are poorly toleranced, and can contribute to this type of problems..... I'd REALLY like to see this "old" advance unit with multiple indexes..... and a pic of the "new" advance unit might help too... Are the replacement parts all genuine Honda parts?..... Don't give up!....We'll figure this out!.... Steve
 

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alexis159 said:
as I have no clue about what is bad. .
Henry has tried to tell you that you might be running lean (too much air, not enough fuel). If you can't get some original air filters, try running with the choke partially on, which will make the engine draw more fuel than air.
 

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Sensei
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OK...NOW we might be getting somewhere!..... The "old" advance unit is SEVERELY corroded, and it is likely the camshaft end was similarly affected......Even if you "cleaned" the area the advance unit "seats" on, it may allow for "wobble" or "slippage" that will change the advance setting (or allow it to change) while the engine is running..... Did you replace the "key" pin?...And back to my first question....Were the replacement point-plate parts Honda brand,(manufactured by Kokusan or Hitachi) or just aftermarket ones "for Honda"?
SOME cheaper aftermarket parts are nearly impossible to adjust "within specs".......

Once you correct the points/timing so the bike fires EXACTLY on the "F" and "LF" marks, AND advances to within the doubled lines at 3000 and above, it may run better.... I still think you are leaning-out somehow.... (could be a clogged jet, jet passage, crack in the rubber manifold, or many other causes)...Regardless, RECLEAN and adjust the carbs!...(Get kits and replace the o-rings on the jets, reset the float heights, etc...)

ONE often forgotten rule is: Just because a part is NEW, DOES NOT mean it is GOOD!

The picture helped!....Got any of the other suspect components?.....
You REALLY NEED to check compression as well.....
Steve
 

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Discussion Starter · #15 ·
I had to buy a new key pin because the last advance use to loose those pins
I think that is a honda part it had some numbers 286, the point-plate parts as the advance mechanism. the rubber I just change but before even with the cracked It just work better . Maby could be that I should change the jets for bigger ones. I would try to move the timming chain two teeths more to see if I can solv the problem. It's not normal that the bike warm up to fast?.and it doesnt show any black smoke from the exaust.
 

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Sensei
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You SHOULDN't just move the cam chain because you THINK it's wrong!.... Check it and IF it is wrong, RESET it to the correct positioning as specified.... The index marks on the cam and crankshaft are absolutes that MUST be properly aligned when setting the timing chain on....
 

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Sensei
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TO ANYONE more familiar with the 350's.....
Is it possible that the advance center (cammed part) is on backwards and causing this apparent timing being "off"?...... I don't have one handy to look at...
...........BILL?....
 

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Although the 350 advancer is a different part, it's made the same as a 450 advancer - it is possible to put the cam part on 180 degrees off.
Although if you did, it would be very difficult to get it running - not sure if the plate would turn far enough to make up for it or not.
 

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alexis159 said:
I read in some other website that the points should be roughly vertical - if they are not, the cam may be out 1 tooth on the sprocket or the points cam is out. http://home.modemss.brisnet.org.au/~jmi ... 50_04.html
There are a couple of "notches" in the top of the points plate - they should more or less line up with the notch in the cam bearing (point housing).

If the cam chain is off by a tooth or more, you'll never get the engine to run right, if at all.
The cam timing is what it is, and with a stock configuration, it is never adviseable to "adjust" it.
 
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