[Raptor726]

Hi i am new to this forum and am lookin for help i have a 01 raptor 660 with a 726 big bore a raceing cam an edelbrock raceing arb and a bunch of other upgrades... Anyways the quad idles fine and for the most part rides fine howver when i really pin it it will bog and hesitate and then get some power but i feel like its not NEARLY as powerful as it should be it wont even power wheelie nevermind clutch wheelie in 2nd sometime not even in first and is not as fast as i exspected it to be at all it stalls on hills aswell im very fustraded ive tryed tuneing the carb and normal stuff carb is clean as hell valves dont seem to be the problem as it starts right up someone help!!!

 

[frozenrider]

Who did the engine build? What cams? Jets?

 

[Raptor726]

Diggen raceing which is one of te best places to go on longisland not sure the type of cam the carb is jetless its edelbrock the quad itself is the cleanest 01 ive ever seen in my life lol

 

[Dog86]

Why did they run a edelbrock carb? Never heard much good about them. FCR's are the ones to upgrade to on a 660 but unless your in the 65+HP range stock carbs will do fine. Did you just have this work done? You can bore and stroke a motor as much as you want but all the power in these motors is made in the head cam combo assuming you have a good single like Sparks or CT or a set of duals.

Need to know if your running a air box, what cam and what exhaust, porting that is done. For the work that has to go into a 727 big bore with splitting the cases to bore out the cases to fit the bigger sleeve the money is better spent on other upgrades like porting and such. What compression piston are you running? Do you still have the stock carbs?

 

[close2stock]

+1 on what dog said... I've never like the edelbrock stuff to much... The head and cam is where ur power is gnna be made at...

I know on my 686, having the airbox lid on or off is like night and day.... Give a lil more info on specific specs of motor....

 

[Raptor726]

I traded a grizzly for it the work was done a few mounths ago the guy at diggin said he doesent really remember even putting the carb on which leads me to belive the guy i got it from decided to do i himsel causeing all these problems i run an open airbox ive tryed both havent seen much diffrence but then again the lid looks like swis cheese all i know is its built right if its built by diggin but im begginin to think its this stupid carb its like 39 or 40mm but aret stock 2 30mm ones???

 

[Raptor726]

Also the pips clmeing feom the engine glow red when the quad is runnin is this normal

 

[Raptor726]

Its a 105mm bore 5mm stroke 12-1 compression

 

[Dog86]

I am betting the carb is the issue. IIRC that carb flows less then the stockers. On a 105 bore with a 5mm stroke it would be like a 770 motor I think. That carb can not feed that big of a motor. Thats not a common crank either. I think Powroll makes a kit like that, that use to be common back in the day but it was before I was riding a Raptor. They even say FCR's are installed but they probably went with the single because of cost.


Heres a link to there page, sounds like the kit to me. POWROLL PRODUCTS FOR THE YAMAHA RAPTOR 660


I bet your running to lean because it can't feed that big motor. 770 is a big motor for sure.

 

[SegKast]

Carb carb carb carb carb...

 

[Bruces_720]

Buy some fcr's get it on a dyno and call it done 95% sure that will fix it.

 

[Bruces_720]

Also what kind of gas are u running and whats the elevation?

 

[HK45nut]

FCR39's with a mix of gas. I am running 12:1 and 3 gallons 91 octane and 2 gallons 108 octane, works out to be about 96-97 octane. I will be going to 110 as soon I am out of what I have. I can get it cheaper than my 108.

 

[Raptor726]

Well if thats te kit why is it not an fcr carb and do you think it could be that im only runnin 104 octane not 112? But i guess that wouldent exsplain the stalling on hills and shit so i guess it is a 770 guess the guy at diggin wasent thinkin very har when he said that it was a 726... So u think i should get some stock carbs

 

[Raptor726]

Soo you think i can get away with stock carbs or should i can fcrs if so how much are fcrs and what model do i get

 

[Bruces_720]

There are 35mm and 39mm FCR setups the 39's retail for $1200 but u can usuallly get them for around $800 if u look around enough. SOmetimes cheaper, if u could find a good set of 35's your bike would run good on those. But if your gonna pay the same price go with the 39's so if u upgrade in the future. U may be able to get by with stock carbs but its gonna be close i think. But u can probably get some stockers off ebay for around 100 maybe so u might be better off getting stockers and putting like 170,175 jets and a 25 or 27.5 pilots and go from there on a plug check read. :thumb:

 

[Bruces_720]

Also with the fcr 39's u will need an offset billet intake to make them fit in the frame and u can get those for $120-140 but there billet and fit good.

 

[Raptor726]

And you dont think i can get it running good with the edelbrock?

 

[Dog86]

If it was a smaller motor you might but if its really that size of motor then no I don't think that it will feed enough on the top end. If your not looking to spend to much money on it I would just run some stock carbs with a get kit and open air box with filter kit. You will probably be able to sell the single carb and make your money back on the stocker if not more. The single carb is OK just not for big motor they seem to do ok on stockish motors.

FCR's are very nice carbs though, What exhaust do you have? Some won't clear the FCR's so keep that in mind to.

 

[Raptor726]

Im running a gytr exsaust i already have an aftermarket intake this quad is essentially aftermarket everything down the the rims haha but uhh ehat manafolds do i have to buy to make the stockers fit and what jet kit should i get