losing throttle response on with my 00 SRX

[CAM2]

00 SRX losing throttle response

A friend I went riding with last weekend told me about this site and I have been reading alot of interesting posts. I love this place! Anyway, I just bought a 2000 SRX and the power is awesome. My first question is that It has shaved and domed heads (the seller also gave me the stock heads). one of my questions is what precautionary methods should I take to protect myself from frying my pistons with these heads? I have been running 93 octane and adding Klotz octane boost in it. Second question, I rode 140 miles last Sat. and it seemed to be ok with only one problem. It would be runnin along fine, but once in a great while I would lose all my throttle response, then once the sled stopped it would idle about 3 grand, I would keep blipping the throttle and finely it would fall to 2 1/2 on the tach and I would take off. like I said it only happened once in a long time and other than that I had no problem with motor hesitation or anything. I called one of the Yamaha snow dealers here and they suggested cleaning the carbs. I would think if the carbs were dirty it would act up more the once in a while and I had great throttle response. Last but not least, I noticed that my picks (which are brand new from the previous owner) have been slightly digging into my rear heat exchanger. What can i do to prevent this? Any help would be greatly appreciated.

 

[mrviper700]

sure sounds like the sled is lean to me, thats what happens when the tach hangs up and doesnt return back to idle, I bet the problem occured when you were steadily cruising around 45-55mph, you are on the needle circuit of the carb and its most likely very lean here, I would take a good hard look at the piston top and check the front edges of the piston, they will begin to remove the upper ringland. I would reinstall the stock heads if you dont know what the measurments are on the heads and if the squishband has been recut to allow for the increase in compression, the 00-02 srx are already tighter clearance then the 98-99's were. There is nothing wrong with running modified heads on pump gas as long as they are set up correctly, this requires the heads to have the squishband cut and the angle changed to run cool enuff to not have detonation.

 

[waldo]

Next time it feels "funny" pull your choke up half way - Sometimes you may think its rich but its really lean surging - very bad! If it runs crisper or better and dosent fall on its face - your lean. Its lean from what you explain fur sure - Do you know how to do a piston wash check?? - The best advice is to go back to stock unless you know how to tune it in - these sleds do not like higher compression for trail use!! and they dont go that much faster with higher compression compaired to what its worth. But if your like me - you'll have to learn the hard way ($). or just spend it on an EGT right now and port it - (if its not dammaged already) - do a compression check right now - You should be around 125 (stock) or so. higher compression is NOT the way to make a sled faster for trail use - Well - it will go faster for a little while. The key is a race porting with trail compression (or less). or run race gas - its about the same cost as premium and much cheaper than jugs and pistons - race gas will slow you down though. so your almost back to where you started.