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Post by byufanatic on Jul 14, 2008 19:51:14 GMT -5
I hooked up a timing light and have some more information - but all it's doing is confusing me. So if someone can shed some insight, that'd be great. Here's the info: The plug is firing at this point: According to the manual, it should be firing directly on the "F" mark when idling. As you can see, it's not. The manual also states that the timing should advance as the RPM is increased. I'm guessing (from my interpretation of the manual) that the "T" mark should be aligning with the tab at 3000 rpm. I don't have a tachometer, so I can't verify when it's at 3000 rpm, but I do know that when I crank the throttle and rev up the engine that the timing mark doesn't budge. It stays rock solid at the mark in the picture above. So, this suggests to me that the piston is still traveling upwards when the plug is firing. Thus, this is likely the source of my current problem. Basically the plug is not firing at the right time (according to the manual) and the timing is not advancing when the engine is revved. I did this with the engine cold (and was running better) and when the engine was warm (and has no power). The timing position is the same. If I'm right, then how in the world am I supposed to fix this? Rob
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Post by byufanatic on Jul 14, 2008 21:48:47 GMT -5
Update -
I put the original CDI back in. This one worked a little better. The plug was firing closer to the "F" mark and when revving the timing advanced. But, I'm still confused... should it be moving TOWARDS or AWAY from the "T" mark when increasing RPM? In my case, it was moving away.
I took it for a spin and it had better response, but same problem when it got warmed up - no power. Didn't get a chance to check the timing at that point. I'll try again tomorrow.
Perhaps it's still the TDCs (the one on the valves and the one on the engine) still aren't properly aligned. I still dont' know if the TDC mark on the valves should align with the "T" mark or the "F" mark on the engine.
Rob
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Post by byufanatic on Jul 15, 2008 13:47:42 GMT -5
False alarm on the TDC issue. It appears that when I had set TDC on the flywheel to take the picture the flywheel moved a bit while I wasn't watching. (It doesn't stay at TDC itself, you have to hold it in place.)
So, after having my son hold the flywheel at TDC I eyeballed the valve cam and it is very close to TDC as well (perhaps just a couple mm off at the most).
So, scratch that as a possible cause for the problem.
I'm still very much open (and desperate) for ideas/solutions.
Just to recap -
It was running fine - getting up to 32mph. Went to run errands, came back outside to start the scoot. It idled fine, but would not rev up properly (bogged down) and had no power at the wheel (you could feel the belt tugging a bit, but wouldn't go). Managed to get it home, but since that point when I start it cold it'll run (top speed of 20mph) but once it warms up, I have no power at the wheel. However, if I use a blower to force air into the airbox it will rev up.
What would cause it to suddenly go from a nice, smooth 32mph (warmed up or cold) to sputtering at 20mph cold and bogging down with no power when warmed up?
Rob
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Post by imagesinthewind on Jul 15, 2008 14:11:11 GMT -5
auto choke stuck on?
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Post by byufanatic on Jul 15, 2008 14:34:21 GMT -5
I pulled the auto-choke and tested it. Worked according to the testing protocol. But, on the scoot itself there's no way to tell if it's doing what it's supposed to do.
Testing protocol for auto-choke:
Remove from carb. Hook up to 12v battery. Needle should extend 3/8 inch within 5 minutes.
Rob
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Post by imagesinthewind on Jul 15, 2008 15:01:50 GMT -5
didnt you say it was really hot to the touch? What if it's not turning off all the way and still giving the engine too much fuel. The extra air blown in would help use that extra fuel-thereby making the engine roar to life?
Try taking off the left side panel and when it starts to drive bad, unplug the choke from the electrical and see if that helps?
BTW, I think it's just you and me now. . .
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Post by byufanatic on Jul 15, 2008 15:33:28 GMT -5
I found out why they get hot to the touch - there's wax inside it. It's supposed to get hot (and expand) and thus push the needle out. When it (the engine and the wax) is cold the choke is ON - getting extra fuel to the engine. When it warms up, the needle in the choke is supposed to extend into the carb (no longer chokes).
If you unplug the choke you're turning it "on". So not a good idea to unplug it.
I hope it's not down to you and I. *smile* I'm totally stumped. But, keep throwing out ideas! Two heads are always better than one.
Rob
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Post by Enviromoto on Jul 15, 2008 15:56:37 GMT -5
So let me get this straight.
You set your valves to .004 intake and exhaust on the compression stroke?
Cleaned your carb and inspected the diaphram and intake gasket?
Set your fuel mixture to 2 1/4 turns out?
and have checked all your vacume and intake connections for leaks?
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Post by imagesinthewind on Jul 15, 2008 15:57:31 GMT -5
Oh, still doesn't sound like it's turning off though.
Where in Tx are you? I spent two years in Austin and 5 years in Dallas.
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Post by byufanatic on Jul 15, 2008 16:30:00 GMT -5
So let me get this straight. You set your valves to .004 intake and exhaust on the compression stroke? Cleaned your carb and inspected the diaphram and intake gasket? Set your fuel mixture to 2 1/4 turns out? and have checked all your vacume and intake connections for leaks? Yep (to all the above). Rob
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Post by byufanatic on Jul 15, 2008 16:33:33 GMT -5
Oh, still doesn't sound like it's turning off though. Where in Tx are you? I spent two years in Austin and 5 years in Dallas. I agree. That's why I went and got a GRABIT to get the choke off the carb (the screws were stripped by previous owner). Still, despite operating properly OFF the scoot it might not be operating properly ON the scoot. Well, despite having inspected and cleaned the carb several times, I'm gonna boil the carb. I don't know if that'll fix anything, but at this point I'm borderline psycho. *grin* I'm in the Austin area. Rob
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Post by imagesinthewind on Jul 15, 2008 17:11:30 GMT -5
Now it's time to start looking at things it CAN'T be, like the wire to the turn signals. . .
What does boiling the carb do? Won't carb cleaner clean it well enough?
I used to live just off Riverside Dr. Chevy Chase Apts. I own a bar I named The Back Room after the music venue on Riverside. I managed the Dominoes on Riverside in the 80s.
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Post by byufanatic on Jul 15, 2008 17:24:43 GMT -5
"Boiling" the carb is when you use extremely strong cleaner. It's so strong that it will eat through non-metal (so you have to strip all of it off the carb). If there's any gunk in any tiny little corner of the carb somewhere this will fix that.
You can take it in to a mechanic and have them do it, or you can buy it in a can. (I'll be buying a can of the stuff.)
Cool. Sounds like you had fun here in Austin. I've been here for a couple of years, but also lived here for a couple years way back when I was a kid in elementary school.
Rob
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Post by imagesinthewind on Jul 15, 2008 21:02:42 GMT -5
Good luck with that. I'm giving up on mine. Can't understand why just taking off the carb and replacing it ten mins later would cause it to not start.
I work on 5 cyl diesels for cripes sake. Never had trouble like this.
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Post by byufanatic on Jul 16, 2008 1:17:48 GMT -5
I'm not ready to give up on mine just yet - Partly because that's just my personality. I might moan, groan, and complain, but I can't resist a challenge (and this is definitely a challenge). Also because this scoot will become my primary mode of transportation if I can get it going. My purpose for buying it was specifically to save on gas. And finally I just can't walk away from it. I've invested too much time and money in it. I've got the carb boiling now. I'm gonna leave it overnight. Actually, I have two carbs. I took my spare and stripped it down (already had it off the scoot). Boiling a carb is really a rather simple process. It's just a matter of taking EVERYTHING apart and being sure to not put any NON-metal items into the can. Here's a picture of my carb stripped down: I know it looks like a very complex thing, but trust me, it's not. See how I even grouped things together? Here's a picture of the things that I do NOT boil: Oh, one thing that is missing from the picture - the air mixture screw. Don't forget to take that baby out so that the chemicals can get in there real good (be sure to put the screw in the chemicals with the rest of the carb too). The air mixture screw has a very tiny washer behind it. Be sure not to lose it!!! If you decide to boil a carb, call around to see which local parts store has the chemicals. They usually come in 1 gallon and 5 gallon sizes (1 gallon is plenty). I got "Chem-Dip" for $20. This stuff is MUCH stronger than what you pour into your carb or into the gas. Rob
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Post by imagesinthewind on Jul 16, 2008 11:38:08 GMT -5
You know, at the end of this, this thread need to be a sticky. You've worked so hard and so long and in the end you will have bonded so well with this scooter. And it's a great tutorial on just about everything on scooters. An interactive GY6 Manual, if you will. Good luck, I hope the scoot comes to life for you. Ever think about taking the entire engine and software off the scooter, take it all apart, clean it and reassemble it like it was new? Wha about exhaust? What if a small critter got in the exhaust and build a nest in there? I know, now I'm being ridiculious. But when you lose something and you cannot find it you start looking in the obvious places. After that doesn't work you start looking in places it can't be like behind the upstairs toilet! LOL!
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Post by byufanatic on Jul 16, 2008 14:12:15 GMT -5
LOL. I suspect this thread will never come to an end (as long as I have this scoot).
Ugh. I don't think stickying it will be a good idea. It is so convoluted and jumps all over so badly that unless someone has followed it from the beginning (and even then) it's too hard to follow and understand. (Sorry Tortoise!)
However, perhaps starting a new thread with a nice, neat flow might be a good idea.
Disassemble EVERYTHING? Double-ugh. I've done that with my motorcycles before and it is a BIG job that requires a lot of time and space. When I did it back then I would do it on weekends and I did it in the garage so that I could categorize everything in order to put it all back together. I'm living in an apartment now so I don't have that luxury.
Ok, latest update -
Carb has been boiled. I pulled it out of the can, patted it dry with shop paper towels. (I LOVE those blue paper towels!) Put it all back together, and stuck it on the scoot.
But, before I did that, I pulled the intake manifold to double-check (again) for cracks. This time I noticed a lot of moisture (gas?) on both sides of the plastic spacer. Weird. The bolts were still snug so not sure how that could have got there. Put the manifold back on and tightened it even tighter than before for good measure - but careful not to break the plastic spacer.
Still handles the same - slowly climbs up to 20mph-ish. But, one CRUCIAL difference - after it warmed up it STILL HAD POWER. Whoa! Progress!
After riding it around a bit it got just above 25mph (according to the speedometer).
I opened up the air box to see if that would help. This caused major hesitation if I opened the throttle too much too fast, and had no impact on the top end speed.
I'm gonna wait for it to cool down and I'll open up the CVT and check to see if perhaps I put something together wrong when I replaced the belt. I read in another thread about taking out two rollers (opposite from each other) so I think I might try that as it kinda feels like it's going to a higher gearing before it's ready (or it could still simply be low power issues).
One thing I did notice is the scoot seems to "hum" a bit when I reach higher revs when the bike is on the centerstand. I didn't notice that before I replaced the belt.
Skipp and Jeremy (and others) - I really value your input guys. Even if you don't know the answers, some "maybe try this ..." comments would be appreciated.
Rob
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Post by indy50 on Jul 16, 2008 15:11:39 GMT -5
Rob, I've just read all the pages of your ongoing saga and if youve got good spark, vucuumand everything is sealed good.............im starting to wonder have you checked compression? I know you have swapped cdi's , thats what I thought your problem might be. from what you say it does sound like your engine is running lean tho. after your next ride pull and read your plug. You can as others have , remove a couple rollers but I dont reccomend it. I know people who have with no bad results. The thing is you arent going to gain any top end lightening your weights although you may increase rpms I've been pretty busy the last couple days and havent had much time to hang here. If all else is in order , try your other carb & see whats up.
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Post by byufanatic on Jul 16, 2008 17:59:23 GMT -5
Hey Indy!
Good to know you're out there still. *smile*
Yes, I've got brand-new vacuum and fuel hoses. I've also checked compression several times. Right now it's around 125 psi.
I swapped out the CDI, but it didn't make a difference. When I hooked up the timing light, I noticed that the ignition was not advancing. So, the CDI I put in is apparently bad. I put the original back in and now the ignition advances.
The carb has been completely stripped down to each individual part and boiled overnight. So it's nice and clean.
In a little bit I'll take the scoot out and drive it up and down the road with WOT, then cut the ignition and check the plug. It was running rich before, but who knows what's up now that the carb has been boiled. Ha ha.
As I mentioned earlier, after boiling the carb and checking the intake manifold again I've made progress - I no longer have loss of power when the scoot warms up but I still slowly top out at 20-25mph (used to top out at 32mph).
Rob
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Post by imagesinthewind on Jul 16, 2008 18:06:45 GMT -5
I top out at 25, too. But not slowly. I get there pretty fast.
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Post by byufanatic on Jul 16, 2008 19:58:48 GMT -5
Put the original exhaust back on, put a spark plug socket in my back pocket and my camera around my neck and took my scoot out for a spin. Definitely does NOT want to get above 25mph (this time best I could get was 22-23mph. I didn't do a very long run because I didn't want to risk breaking down and getting stuck miles from home. So I basically went up and down the street a few times (about 1/2 mile each way) with WOT. Here's my plug: Looks reasonably ok. I'd like to take it out for a longer, more extended run to get a better plug reading. Earlier I had swapped the original CDI with another one that I had and it appears the other CDI was bad. I had also swapped out the coil. I'm going to switch back to the original coil. Even though they both showed decent spark when testing on the centerstand, it could be wimping out on me at higher revs. I know that the coil doesn't compare to that of a car. I hooked up my timing light to it and it has an "ok" light but if I rev it too high then the light stops strobing. I'm guessing because there's not enough juice in these coils to keep the timing light working at higher revs? I remember reading a post somewhere that these coils put out around half what a automotive coil produces. In any case... seems that I have (sort of) resolved the no-power issue and am now trying to figure out why I've lost my top speed. Rob
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Post by byufanatic on Jul 17, 2008 0:55:29 GMT -5
Ok... I have a very SERIOUS bone to pick. I mean, it's hard enough that we're dealing with sub-standard quality, less-than-optimum customer service and warranties, and manuals written in chinenglish. But when we have to deal with glaring errors like this one: According to the diagram above, they say spring first, then vacuum plate, then cover. I have two carbs. I took them both apart and on both of them it was vacuum plate, spring, cover (in that order). So which is it? spring - plate - cover or plate - spring - cover If the manual is wrong (it's supposed to be plate - spring - cover) then I'm not very happy with the pinhead(s) who put the manual together. If the previous owner(s) are wrong (and it's supposed to be spring - plate - cover) then I'm not very happy with them for screwing up BOTH carbs and totally confusing me. In either case - one of these pinheads is responsible for wasting my time and efforts. Rob
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Post by bc on Jul 17, 2008 1:19:57 GMT -5
Rob, whenever you soak your carb in cleaner, you need to take an air compressor and blow out all the tiny passages in the carb body. The chem dip will soften up any crud in a passage but doesn't necessarily remove it. Even if you don't soak it, still blow out all the passages.
Good luck.
By the way, I'm following this cause I have a Maui 50 that may bog down and stop every once in a while when you take off. Sometimes it bogs down and doesn't want to go over 15 or 20 for a few blocks. The rest of the time it accellerates on up to max speed of 37-43.
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Post by byufanatic on Jul 17, 2008 1:38:20 GMT -5
Hey BC!
Thanks for the tip. Yep, after I pulled the carb out of the dip I blew out the passages and stuck a copper wire into every hole I could fit it into.
Hopefully someone can shed some light on the air cutoff valve situation for me.
Good luck with your scoot. These gremlins are a pain!
Rob
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Post by byufanatic on Jul 17, 2008 9:47:59 GMT -5
Ok...
I had an old motorcycle service manual that I've kept (I knew it would come in handy someday). I checked the carb diagrams and pictures in that (the carb designs are somewhat similar to our scoots) and it shows:
plate - spring - cover
So, I think it's probably safe to say that whoever made the scooter manual is the pinhead.
Now back to the loss of top speed issue....
Rob
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Post by byufanatic on Jul 17, 2008 16:02:01 GMT -5
This afternoon I took the scoot for an extended ride.
I noticed a couple things:
1 - It seems to rev a bit high at low speeds (as if it's a weak little engine trying to move a big vehicle - which in this case might be normal).
2 - Once it gets up to around 20mph it just chugs along - as if that's all the power it is capable of providing. It's much different than your scoot Ginny. You rev right up to 20mph and feel like it wants to go faster. In my case it feels like 20-25mph is all the engine is capable of giving.
During the ride I cut the engine and did a plug reading. Same as yesterday (see picture of my spark plug above). So, it's not too lean and not too rich. As Goldilocks would say - "It's just right!"
Got home and swapped back to the original coil (forgot to do that). The previous problem (sputtering and bogging down when giving it throttle) came back. "Ah ha!" I thought to myself, "The original coil is apparently bad, and perhaps the second coil is slightly bad as well!"
Put the second coil back on. Still bogging down and sputtering, but at least I can get going from a dead stop. If I roll on the throttle too much it bogs down and won't rev. If I slowly roll the throttle on then it'll rev up (after a moment's hesitation).
So, cleaning the carb seemed to help, but I don't think I'm even touching the source of the problem. Maybe I got two bad coils? Or two bad CDIs? I'm just grasping at straws again. How does one test the CDI and the coil anyways?
Ideas anyone?
Rob
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Post by byufanatic on Jul 17, 2008 17:40:15 GMT -5
Indy -
You were mentioning in another thread about your CVT cover used to be hot to the touch when you upgraded your engine, but now that you cut slits into the cover it's just "warm."
One thing I'm noticing is that after going for a spin my CVT cover is HOT to the touch. Can't touch it for more than a second or I risk burning myself.
I'm wondering if this might be my loss of power issue - the drive train may be taking excessive engine power in order to get the scoot rolling.
Some feedback from everyone please - is your CVT cover hot to the touch (can't touch it for more than a second) after a ride - even a short one of a couple miles? Or is it just "warm" to touch?
Rob
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Post by byufanatic on Jul 17, 2008 19:30:41 GMT -5
More on the CVT -
I just pulled it apart to take a look. Belt dust everywhere (I had pulled it apart and cleaned it out really good about 15-20 miles back). The belt still looks new, but obviously it's wearing very quickly.
On top of the belt there is a groove being worn out where it's rubbing against the starter (looks like when the variator is completely closed together it pushes the belt up against the starter. It's not too bad, just a small groove, but it is an issue that needs to be addressed.
Pulled everything part in there, checked it out, cleaned off the belt dust, and put it all back together. I didn't see anything wrong (other than lots of dust and the rubbing against the starter).
As an experiment, I removed two rollers on opposite sides from each other. It definitely makes a difference! You get up to speed much faster. And, because my scoot seems to be struggling against something that is killing top speed it actually went just a bit faster. It accelerated up to 20mph pretty quickly and topped out at around 27mph (on speedometer)
Rode it around the neighborhood for a couple miles. There is still the hesitation when starting from a complete stop and it's better to slowly roll on the throttle rather than cranking it wide open to minimize sputtering and bogging down.
When I stopped, after just a couple of miles the CVT cover was HOT to the touch again. So, I'm thinking that's also something that needs to be fixed as well.
Rob
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Post by Enviromoto on Jul 17, 2008 20:17:20 GMT -5
DUDE!!!! Stop riding your scooter.
A. Your belt should never touch your starter benix. EVER. That is more than likely your problem. Hit me up in a pm for a nice racing variator I just got in from MRP. $65 Shipped.
B. Put your 2 rollers back in! I have seen variators fail due to extreme pressure on the other four roller plates and can cause a failure. At speed that means the broken pieces jam in your clutch and causes the rear tire to lock up _
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Post by byufanatic on Jul 17, 2008 20:53:19 GMT -5
Hi Jeremy!
Glad to have you chime in on this thread. I'm in need of serious help.
No worries about the rollers. I just took them out as an experiment and plan to put them back in. *smile*
Thanks for the deal on the racing variator. Right now I'm holding off on buying more stuff for this scoot. I've already thrown more money at it than what I spent to buy it. So it's basically eaten through any spare funds I have and payday ain't for another week (which isn't much on a teacher's salary anyways).
I find it really odd that the belt will touch the benix. That means the belt is climbing to the very top of the variator. (And then some!) The belt is a very tight fit when I assemble everything together so the belt isn't too big.
The groove on the top of the belt is very, very small (maybe a millimeter in width and less than half a millimeter in depth). So would it really be responsible for that much heat? We're talking about a LOT of heat in a very short amount of time.
The engine is bogging down without the tire spinning (or spinning at slow speeds) so I don't know if that bit of friction (belt against benix) is causing the hesitation upon acceleration.
I just checked out the old belt (still have it) and there is a tiny bit of wear on the top (nothing real noticeable unless you look for it) so I don't know if rubbing against the benix caused failure or not since I rode it for a lot farther than I have with the current belt. However, the old belt doesn't look that bad so the excessive heat is likely what caused it to break.
If I need to, I'll put a washer on the variator to keep the belt from rubbing on the benix. Maybe I'll even just pull the benix off and simply kick-start the engine. When it's cold it will usually kick start on the first or second try very easily.
The two issues I'm having at the moment are:
1 - Engine hesitates and sputters / bogs-down on acceleration from idle and has lost 10mph on the top end.
2- CVT cover gets extremely hot.
I don't think they are related because #2 has been happening ever since I got the scoot (about a month ago) and #1 just started happening last week.
Rob
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