Put my Sparks key in tonight, will be taking it back out tomarrow

[alping45]

I put the sparks key in tonight and I'm not too pleased with my results. It seems to rev up quicker and goes pretty nuts in mid to higher RPMs, but it really seemed to soften my low end power/throttle response. Before I put the key in I could easily roll into a 3rd gear wheelie on flat pavement sitting down and hold it easily in lower rpms, now it just wont happen uless I stand up and tug or rev it way up and I have to keep it in higher rmps to stay up. And its definately running hotter because once my fan kicks on it almost never shuts back off, and before the key it was hardly ever on. Has anyone else had similar results? Has anyone had to do anything diff with their jetting after the key? I spent weeks tuning my carb in with my current mods until it was spot on and it ran amazing, can't imagine advancing the timing would affect the jetting could it?

[ae13291]

you lost low end?? do u use like 85 octane?? there is no way u lost low end. is ur engine pinging? or did u not turn the flywheel all the way to the left?

yeah something isnt right because it adds a lot of snap low down. I could wheelie in 3rd gear just nailing the gas and pulling back. Before I could get the wheelie going a little bit then it would drop. With the key even if I wasnt trying to wheelie the front would hover a little bit just banging gears into 3rd. You can tell i've gained weight because it wont get up there like it used to, either that or the engine is just getting tired lol

[alping45]

Im running 93 octane, runs smooth no pinging. Im not saying it runs like crap now, it still runs great, but the low end just isnt what it used to be. I did turn the flywheel all the way to the left, even if I didn't its not like it would have decreased the timing, it would just be stock, so I just don't get it.

[ae13291]

Originally posted by alping45
Im running 93 octane, runs smooth no pinging. Im not saying it runs like crap now, it still runs great, but the low end just isnt what it used to be. I did turn the flywheel all the way to the left, even if I didn't its not like it would have decreased the timing, it would just be stock, so I just don't get it.

its just in your head man, the timing key was my first mod, it made my quad alot more snappier and better throttle response, and it did not make the engine run alot hotter? it would probably increase temps by a few degrees. also check your spark plug since the engine combustion will be higher pressure, if its old replace it and gap it correctly

[alping45]

I thought it was all in my head too until I tried a wheelie, that confirmed it.

I'll check the plug but it isn't too old I bought the quad new last may.

All I can figure is that maybe the flywheel turned back to the right some when I tightened the bolt back down. I will check before I take the flywheel off, I should be able to see it in the keyslot.

Since 10° advance is a 70-100° C increase... from my guess 6° advance would be 30-60° C increase. Just figuring each degree would be about 10° C internal combustion temperature increase. Thats not bad at all for what your gaining. I'm curious to see if you take out and claim its more power without it. For me, I noticed no increase in temperature. I run it even harder for longer and honestly I cant see a difference in heat compared to stock. I run a 15w-50 synthetic oil, DPR9Z spark plug, and its jetted to perfection. No problems with heat unless i'm drag racing uphill in 90+ degree weather high RPM run after run and sand puts a lot of stress on the motor.

[alping45]

Originally posted by FlewByU352
Since 10° advance is a 70-100° C increase... from my guess 6° advance would be 30-60° C increase. Just figuring each degree would be about 10° C internal combustion temperature increase. Thats not bad at all for what your gaining. I'm curious to see if you take out and claim its more power without it. For me, I noticed no increase in temperature. I run it even harder for longer and honestly I cant see a difference in heat compared to stock. I run a 15w-50 synthetic oil, DPR9Z spark plug, and its jetted to perfection. No problems with heat unless i'm drag racing uphill in 90+ degree weather high RPM run after run and sand puts a lot of stress on the motor.


Do you mean 30-60° C or 30-60° F? Because 30-60° C would be a pretty good amount. I also run 15-50 full synthetic, just have the stock plug though. Do you notice a difference with the DPR9Z?
Now that I think about it, I've only had the fan for a week and it might just be on more because its been a little warmer out, and I really haven't had a whole lot of ride time to make a good comparison. I also forgot that I had a temp sticker on my oil tank and it seems to be running in the same range, around 180°-200° F.

I think the first thing I'll do is make sure the flywheel is turned to the left, I guess it could have turned with the bolt when tightening it back down.

[alping45]

Oh and did either of you guys make any jetting changes after the key? I really don't think it would be necessary but just want to rule it out, I know I had mine spot on.

I used C for Celsius. That isnt a lot for a motor. The next coldest plug is for temperatures 70-100° hotter and so on so for every 70-100° increase you should get a colder plug. The DPR9Z is colder and for my riding a better plug. I was told short track low end run a 7 or the 8. Desert type riding 9. Its on internal temperatures though. I am going to the NGK 9 Iridium soon. I wanted a regular 9 1st to see if it would foul before I dish out $6+ for a iridium spark plug. Power wise I dont notice any difference with a colder plug but it does help out with cooling. Without advanced timing, higher compression, or a big bore I would not switch to a colder plug stay with the 8.

[Dangerous400EX]

I bet the reason you are disappointed is because you didnt jet up. I am running a 42 pilot and 152 main and it feels REAL snappy, so much that I never want to mess with it again.

What main jet are you running, because running lean will sap a ton of power.

[alping45]

Originally posted by Dangerous400EX
I bet the reason you are disappointed is because you didnt jet up. I am running a 42 pilot and 152 main and it feels REAL snappy, so much that I never want to mess with it again.

What main jet are you running, because running lean will sap a ton of power.


If I remember correctly I've got a 155 main in. I have no problem with the power up top, its real peppy, but I miss my low end.
Maybe I'll throw in a 42 pilot and see what happens.

[Dangerous400EX]

It could be too fat too, check your plug after some riding

[bigbad400]

mine did the same low end boggy thing, but the 42 pilot kicked it back up to were it belongs, i am actually running a kehin 170 main to get rid of the backfire that i got on decel. clip is in the stock possition.

we just got another 8 inches of snow last night, its cold in mi. 30s-40s keep that in mind looking at my jets. also the HMF made me backfire on decel. not the key. i have had the same spark plug in for years now and check it after every ride, DPR9Z, they say its to cold of a plug for my area and temps but i never had a problem, always good color and never wet. i also thaught about the iridium plug but 9.95 is the cheapest i could find them. i can buy 3 reg. plugs for that.