Sophomore Rider
Currently Offline
Posts: 160
Likes: 0
Joined: Feb 27, 2013 22:58:57 GMT -5
|
Post by gy6girl on May 14, 2013 17:34:46 GMT -5
Ok... Here is something I would like peoples opinion on. My scooter started making a gurgling/knocking sound when I would let off the throttle from wide open. Right before it hit idle speed, I would hear a gurgle, then a knock. I figured it was the valves since the last thing I was working on was the carb, and I know it's all good. I pulled the valve cover off, and sure enough, they were not right. The intake was way tight. I couldn't get my smallest gauge in there. The exhaust was way open. I could get a very big gauge in there. So I set them both to... I don't know? What is it? .004? I can't remember the exact number, but it's the right one. Trust me. I'm just not going to get up and go out and make sure it's .04 or .004, or what ever. It's the right one. I think .004... what ever. The scooter now runs a lot better. I actually had an increase in acceleration.The gurgle and knock is gone. One thing... I can hear the valves clicking.  What do you think? Adjust a little tighter? Don't worry about it?  |
|
|
|
Post by hank on May 14, 2013 17:44:30 GMT -5
Hi All scoots will use a different setting depending on your preference and the scoots performance On my  cc bbk scoot i set them at .003 int .005 ex with excellent results A little ticking is perfectly fine, but if its bothers you simply tighten them up slightly Take care and ride safely my friend Yours Hank |
|
Sophomore Rider
Currently Offline
Posts: 247
Likes: 2
Joined: Feb 24, 2013 5:04:18 GMT -5
|
Post by gatekeeper on May 14, 2013 17:55:40 GMT -5
A little clicking noise is no problem. Now if they are going clackity clackity, then they need to be tightened just a little.
|
|
|
|
Post by devo344a on May 14, 2013 17:59:32 GMT -5
After adj valves the motor should sound like a sewing machine thats how mine is
|
|
|
|
Post by onewheeldrive on May 14, 2013 18:05:38 GMT -5
On my 50cc engine:
I set both of my gaps at .003in., and rarely adjust them after that unless I'm having issues. To be fair, my .003in. may be tighter or looser than someone elses adjustment of the same gap. Not everyone's "drag" on the feeler gauge is the same.
With that being said, I think we always hear the valves on these engines. IMO, they "seem" to get louder just from hearing people talk about the sound of valves---- clicky, clacky, tap, tick. Yeah the adjustment itself does change the sound, but our ears are more trained to hear it after doing it.
To sum up the reason for my adjustments: .002in was too tight for both of mine. Depending on how tight my .002in is/was, it may not start because it's too tight, or it may start and run but need readjusted much, much, much sooner than later. I basically worked my way up, step by step(gauge by gauge), from the "spec" .002in. until my scoot would start and run fine and I wouldn't have to readjust them very often at all. I found going past .003in seemed overkill. I've set them all the way from .002-.004in.
|
|
Freshman Rider
Currently Offline
Posts: 86
Likes: 0
Joined: Mar 28, 2013 21:05:37 GMT -5
|
Post by andrewrides1 on May 15, 2013 0:20:26 GMT -5
sure everyone already said it but you must be at tdc when adjusting. that is when the big hole on the cam is facing up.
|
|
Sophomore Rider
Currently Offline
Posts: 160
Likes: 0
Joined: Feb 27, 2013 22:58:57 GMT -5
|
Post by gy6girl on May 15, 2013 1:13:23 GMT -5
Yeah... That's pretty much what I was thinking too.
I am going to play with them again tomorrow.
I think it's the intake that is clicking, I think I will drop it down to .003.
The extra acceleration I got was lost after the engine warmed up, that's another reason I want to try to tighten it up a tad.
|
|
Sophomore Rider
Currently Offline
Posts: 159
Likes: 0
Joined: Apr 8, 2013 11:38:56 GMT -5
|
Post by bwader on May 15, 2013 14:36:51 GMT -5
Mine started doing doing the clanking.
I thought it was the transmission or something was loose in there. After I isolated it taking off the belt and variator and ran the engine I found it came from the engine.
I got it TDC and adjusted to .004 on both. It still makes the noise at idle.
Before I never heard clanking till I adjusted the valves.
So I wreckin' the .003 people are talking about will be better.
Also tightened up the 4 12mm bolts in, one was a little loose. But it didn't take it away.
Its 80'sF today so take longer to cool again.
|
|
|
|
Post by urbanmadness on May 15, 2013 19:48:42 GMT -5
seems like the best clearance is different on each scooter I work on... some like .003 some like .004, others like .002. Since I work on 9 scooters total, I keep a log of what works best on what.... I also note belt sizes, jet sizes and weights.  |
|
Sophomore Rider
Currently Offline
Posts: 160
Likes: 0
Joined: Feb 27, 2013 22:58:57 GMT -5
|
Post by gy6girl on May 19, 2013 11:28:48 GMT -5
Ok.. Here is an update that some might find interesting.
I redid the valves, and it still wasn't right.
I did them twice, once caused clicking and the other time the gurgle came back.
Each time I went to redo them, they were not the way I set them.
Now I will admit that I advanced the engine just by popping the ignition without the spark turned on.
I just moved the cam levers away from the rockers and then gapped the valves.
That's not the best way to do it, but is sufficient. Only something was wrong.
They were not the same when I set them. Maybe bad setting, maybe just heat manipulation.
So I decided I am going to do this one more time, this time I am going to do it right or at least better.
I pulled of the transmission cover and rotated the variator until the engine was in the compression cycle.
At that point, both valves should most definitely be closed.
So I gapped them right there.
I set the intake at 0.003 and I set the exhaust at 0.004 clearance.
I also noticed something wrong with the variator, but that's a different story.
I put everything back together, and it ran beautifully.
No knock, no gurgle, no clicking.
So I took it for a ride and I hit speeds that I rarely hit. The speedometer isn't accurate, but it was pushing 70mph I know.
When I got it that high, and it was still climbing, it started to hesitate at points. Like an engine cycle went around without being ignited.
I think it started running lean at that speed.
It's a 150cc, and right now I have a 110 main jet in there, and a free flow air filter.
I have a 112 that I think I am going to throw in there and see what happens.
|
|
|
|
Post by devo344a on May 19, 2013 13:50:35 GMT -5
Everyone has told me to adj the valves when cold after setting all nite. Ive done this 100 times and at .003 on both they were loose.
So I checked when it was hot (watch the parts are very hot) they were still to loose so I adj while hot to 002 on both Int & exaust now it runs fine no clacking or loud noises.
I never understood why to adj when cold when everyone knows heat expands metal so if there loose when hot is when they should be adj.
If you adj when cold and set them to tight and the valves hit the head it bends them.
I guess we do alot of things backwards why not valves.
Cant wait for every one to tell me how wrong I am lol especially Alleyoop just kidding Alleyoop
|
|
Sophomore Rider
Currently Offline
Posts: 160
Likes: 0
Joined: Feb 27, 2013 22:58:57 GMT -5
|
Post by gy6girl on May 19, 2013 15:50:33 GMT -5
I agree.. It does seem weird. This last time I did them, I adjusted dead cold, but I see where you are coming from. If the engine is warm, all the metal will have expanded to it's natural state when warm. Warm is the state that the engine will be in when it is running. So Why would you not adjust the valves in the state that they are going to be in when running? Beats the out of me. Maybe it's all BS. |
|
cc bbk scoot i set them at .003 int .005 ex with excellent results
