Elite SR 50 - Premium Gas?

sfzoo · Post by **sfzoo** » Tue Mar 18, 2008 5:12 pm

Hello,
Not sure if this is the proper forum, but i meet the requirements.
a) my Honda is running
b) it goes well over 15mph.

ok, here goes:

I bought a Elite SR 50 recently. The guy who sold it to me said it was a high performance machine with a Malossi Racing Kit (whatever that means). and he gave me this list of parts:
-72cc Motor Kit
-Carbon Race Reeds
-Carb Kit, 28mm
-Varator Kit
-Belt
-High End Gear Kit
-Heavy Duty Clutch Springs
-Varator Spring Upgrade
-Carb Filter Kit
-Clutch Weights

It was running extremely well up until yesterday. The only thing that I did differently was when I gassed up I used Premium Gas rather than Regular.
It still runs. It is still fast. But, when i start it up while its on the kickstand the back wheel is moving as if the throttle is stuck. Once I get it on the road i can get up to 30mph WITHOUT touching the throttle, even uphill! I got home today from about 5miles away without once using the throttle.
The sound that the bike makes when i stop at stop signs is unsettling. It is as if i'm holding the breaks and throttling at the same time.

I am super new to keeping a scooter. I know very little. Please help me.

berreta22 · Post by **berreta22** » Tue Mar 18, 2008 5:44 pm

My guess is your idle has to be turned down..you are prolly running rich with that kind of power.

Kenny_McCormic · Post by **Kenny_McCormic** » Tue Mar 18, 2008 5:48 pm

IIRC higher octane=need higher fuel to air ratio for proper burn, plug chop before you burn something up.

sfzoo · Post by **sfzoo** » Tue Mar 18, 2008 6:55 pm

IIRC higher octane=need higher fuel to air ratio for proper burn, plug chop before you burn something up.

what does 'plug chop' mean? really, i have no clue.

PostPosted: Tue Mar 18, 2008 12:44 pm Post subject:
My guess is your idle has to be turned down..you are prolly running rich with that kind of power.

'running rich' means?

thanks btw, but still i am lost as to what to do.

Kenny_McCormic · Post by **Kenny_McCormic** » Tue Mar 18, 2008 7:06 pm

First pull out the spark plug, look at the inside of it, what color is the insulator? If its white or lighter than a coco brown you are lean AND BLOWING YOUR ENGINE!!!

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
ENGINE TUNING
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

READING SPARK PLUGS and JETTING and PLUG CHOPS

Two stroke engines are sensitive to the level of heat inside the engine.
The main jet size in the carb is the main determiner of how hot the engine runs at wide open throttle.

Too hot and they will seize the piston.
Too cool means they are not making full power.

Engines get the hottest when they are running at wide open throttle making maximum HP.

"Reading" a spark plug is the best way to see how hot your engine is running.
Reading the plug means looking at the ceramic insulator inside the plug and checking its color.
The color will indicate the overall level of heat in the engine.

Reading the plug requires fully warming up the engine by running it for about 10 minutes... Then making a top speed full throttle run for a half mile or more, then killing the motor and stopping and pulling the spark plug on the spot.
That is called.."Doing a plug chop".

When doing the "plug chop"... It is important to chop the throttle and turn the engine off with the switch or key and then pull over to stop... You don't want the engine to idle... that will change the plug color.

You can wait till the plug cools... the color won't change.

The color of a plug on a correctly running engine is a light brown or tan color.
Lighter than that means danger of a piston seizure.
Darker than that is OK... But real dark or wet looking means your main jet in the carb is too big (too rich)... pull it out and look at the number on the side and buy the next size smaller (leaner).

Note... To get an accurate plug reading takes a fairly new plug... a plug with 2 years of crud on it will never really show the true color (or heat) the engine is running at.

Dac · Post by **Dac** » Wed Mar 19, 2008 1:14 am

also, really nice bike.

itzmepete · Post by **itzmepete** » Wed Mar 19, 2008 1:59 am

30 mph without touching throttle, darn, that is not only dangerous but could be burning up your rear clutch. Download manual here on the forum. Check throttle cable adjustment, adjust carb, ur's is different than stock so I don't know but yeah big time, something is not right with the fuel system. Premium should not make any noticable differance. I just filled up with premium after running reg. Higher compression runs smoother with premium, the only differance is higher octaine. I used to run 100LL (low lead av gas) in my 71 Dodge Challenger as I would get it for free at the airport. My Dodge had a 340 bore .030 over 10.5 to 1 compression, moderate cam which was like a step under racing, yeah, that 100LL was magic compared to 93 octain. No ping and smooth in the summer heat, just had lots of lead which meant heads off at 50 to 60k for clean up.

One note, my engine STOCK when started after a few seconds would speed up. If up on its stand, when it started to speed up the wheel turned slightly. Tap the brake and it stopped. Once warmed up is didn't do this. My Big Bore Polini, Nope, starts cold or hot and you give it a rev or two and it idles nice and low.

Maybe your setup is not right, 28mm sounds like alotta carb. A 21 mm sounds better, maybe the jet is wrong size as well. I'd be willing to bet anything if your throttle cable is ok, its your carb PERIOD. Too big, wrong jet, I will guess your pre mixing fuel as well. Have acess to a stock carb that you can rejet? Take apart your carb, maybe the previous owner assembled it wrong.

Carb return spring broke? In any event, there is a video on Youtube on Race Carb repair take apart and adjust. The author did several videos , I'd start there. What did you do riding that at 30 mph with no throttle? You actually got the brakes to stop it?!?!

MySpree · Post by **MySpree** » Wed Mar 19, 2008 9:38 pm

acctually 28 is a great carb for it, a 21 is acctually small belive it or not, you want to run atleast a 28 with a malossi.

stillspeeding · Post by **stillspeeding** » Thu Mar 20, 2008 7:14 am

sounds like the throttle cable is binding.

sfzoo · Post by **sfzoo** » Mon Mar 31, 2008 3:35 pm

Ok,
So i took apart the bike to figure it out, without any prior experience or manuals for reference:)

turns out that the throttle was getting stuck. It was getting stuck where the cables are connected just after the floor board. I sprayed it w/ WD40, and PRESTO.

should i still do the plug chop?

Kenny_McCormic · Post by **Kenny_McCormic** » Mon Mar 31, 2008 3:42 pm

Yes just to be sure everything is OK, and your engine is set up for optimal performance. 90% of 2 stroke engine issues can be diagnosed with a spark plug wrench and a can of foaming carb clean.

stillspeeding · Post by **stillspeeding** » Thu Apr 03, 2008 3:37 am

Did you even bother to check the tranz or the throttle cable before you post, bottom line= know your engine! only when you have checked everything should you then post=master vs rookie

sfzoo · Post by **sfzoo** » Thu Apr 03, 2008 11:50 am

nope!

i'm truly a rookie in the scooter game.

I am learning.

be easy!

thanks