. By rosiemoto (Read 11,517 times)

[Alleyoop]

Cool, if I would have known that I would have sent you 13g Dr. Pulley sliders instead of the 11 gram ones

[rosiemoto]

Aww, makes me wish I could find some use for those 11's, but they were just too light. You said you do trips to FL every so often.. if you happen to be riding through my area we could make the trade? Honestly I don't think I'll ever be able to use a couple of the things you sent, so I figure they're best back in your hands.

[rosiemoto]

Dec 11, 2015 20:54:49 GMT -6 Alleyoop said:

Scoot appears to run pretty good, I would try 12 gram weights for just a little more UMP starting off and a little more RPMS. Also don't forget your 13 weights already have flat spots.

Concerning your valves set them BOTH to .004 inchs, you can get feeler gauge sets at any auto parts store. But watch the sets some start at .008 which are for your bigger motors on cars and trucks. Or if you have a Harbor Freight around you:
Here is one with the sizes you need.
Alleyoop
www.harborfreight.com/32-piece-sae-metric-feeler-gauge-32214.html

Alleyoop, this was back from pg 9 on this thread, but I'm finally getting around to doing my valve adjustment today. I hopefully have the right extension size now. I'm going to set them both to .004 like you said, but I'm just wondering why so many people online in older threads are saying to adjust the exhaust higher than the intake? (example .004 intake, .006 exhaust) Is that outdated info to be doing that?

[Alleyoop]

HAHAHA, no they are just lazy Reason some set the EXHAUST with a wider gap is that is the valve that tightens up much quicker due to the extreme heat the valve with no cooling effect. The Intake gets nice cool fuel plus nice cool air to cool the valve and head area around the valve sit.

With a wider gap it extends the time for the next valve adjustment. What they do not realize is they are limiting the amount of the opening due to the wider gap also noisier motor as well as less power.

So yes, you can go wider if you want I just give the best setting for the best performance from the motor.
Alleyoop

[rosiemoto]

Ah I get it, thanks! Just did the valve adjustment, WHEW that was a 3 hr project, but I'm sure glad I did it because the exhaust valve was nearly FLUSH closed; I didn't have a feeler gauge that could fit, I believe I even tried 0.016! Intake valve was already perfectly at .004 inch, so that was cool to know that stays good. 

Started up the bike, and it stayed right at a constant 2k idle the whole 3 minutes I had it on; seemed very smooth. About to test ride it after a late lunch break! I'll do the Air/Fuel adjustment next, but not today. I want to first see if I can feel any difference in the performance with the valve adjustment.

How often would you recommend to re-check the valves? Was it every 3000 miles?

[Alleyoop]

scooterdoc.proboards.com/thread/11580

[rosiemoto]

Thanks, so it's more an as-needed thing. A couple years ago I used to have a similar problem you mentioned of engine wanting to die; but it ONLY happened after a quick/emergency stop and it would either point blank stall, or it return to idle completely fine but idle high afterwards. Coming to stop signs simply it returned to idle no problem. Only other symptom I can tell was if I stopped the engine while waiting on a train or drawbridge, it would be 50% chance HARD to start needing throttle and cranking like you mentioned.

You know, about the power loss you mentioned, I swore my bike used to be faster years ago, but I figured it because I was 40 lbs lighter back then, so I didn't think much of it. Can't wait to go on a ride (in a few minutes) and see if it pops a wheelie or something...lol joking about that.

[rosiemoto]

Just did a test ride after valve adjustment. Running great! Here's the differences I noticed:

- Warm air puffing out of the exhaust pipe while still letting the bike warm up.. that was different, I only remember my bike puffing out air without a temperature before?

- The throttle is noticeably more responsive, as in no "dead spots" in throttle now. I can feel even little changes in throttle and it feels normal and "linear" for the first time in quite a while!

- The idle is about 500-600 higher now vs before the valve adjustment, and it stayed that way, so I actually had to bring it down. (Therefore using less throttle to idle the same rpm..hmm.. more gas mileage??)

- Coming to a quick stop (sudden yellow lights) didn't cause the bike to idle high like it used to. It seemed like my bike wasn't bothered at all about the quick stop, unlike before where it felt mad at me.

- Stopped engine and restarted it after a 15 min ride and it started right up. It used to give me a hard time restarting it warm.

So it seems the valve adjustment fixed alot of random things! Well considering how badly the exhaust valve was out of spec, it makes sense. My bike had symptoms of running lean before, but they seem to be gone now...

[Alleyoop]

Great to hear the motor is running very well and you actually notice the difference.

Adjusted valves do really make a big difference, many times people will get after the carb trying to compensate for the tight valves. You can many times make the motor run a little better but not near its best. Eventually the valves will need to be adjusted because no matter what you do it will no longer help.

So now you see how important it is to have the valves adjusted when needed. I know it is a pita but it has to be done. The next valve adjustment really depends on the quality of the head and valves and mostly on the quality of the head. The head is what gets compressed with all the banging going on which then closes the gap.
Alleyoop

[rosiemoto]

Here's a comparison shot of how the belt rides on both of my variator fans (108mm and 115mm). You can see a difference in how far the belt reached the edge on both of them.

[Alleyoop]

Yep, on the 115mm it climbed at LEAST 1/4 of an inch more.

[rosiemoto]

Oh... wait, I assumed since the 108 had almost no edge gap and the 115 had a gap it meant they were about the same... no? (Must be because the bigger diameter or something?)

115mm top speed is 6700 rpm. 
108mm top speed is 7000 rpm. 

115mm cruises 40mph @ 5000 rpm
108mm cruises 40mph @ 5300 rpm

115mm wide open acceleration is 5900-6200 rpm
108mm wide open acceleration is 6000-6300 rpm

Between the comparison picture and these results, would you say the 115mm wins?

[Alleyoop]

Question?
On the WIDE OPEN Acceleration after the scoot reachs say 40mph DO the rpms climb or do they stay the same?

115mm wide open acceleration is 5900-6200 rpm
108mm wide open acceleration is 6000-6300 rpm

[rosiemoto]

Good question. After 40 wide open it doesn't really change until about 50mph, then it very slowly goes up. I remember the stock variator rpm would very noticeably climb quickly after 40.

[Alleyoop]

Great then the weights are correct.