My son's raptor 80 from the dealer has always been cold blooded. Does anyone know the stock carb settings? Would rejetting help? Can' t keep the thing idling unless very warmed up. Have to use choke all the time. Please help. Thanks for your help.

 

raise the main jet 5 percent.

 

Actually, you could need a larger pilot jet - I think the stock one is a 12.5. Before you try that though, look on the left side of the carb for a small rubber plug above the idle set screw. Pop the plug out and adjust the pilot screw (you'll see it once you get the plug out). You will want to turn it counterclockwise (I think) to richen up the idle mixture. Turn it 1/4 of a turn at a time, and keep track of how far you turn it. Also, warm the machine up before you make these adjustments, and make sure the choke is off properly - these machines' choke levers actually can be turned too far towards the off position and it causes problems - you should turn it just until it hits the detent, it will go a little more than that , but that's too far.

No air leaks at the carb boots, right? The main jet doesn't meter fuel at idle, so that's not your problem. Rule of thumb for the pilot jet is that if you have to turn the pilot screw out more than 2 1/2 turns (from all the way in), you need the next larger size jet.

Hope this helps. Let us know how you make out.

 

Thanks everyone. After the dealer assured me that the quad was cold blooded, I have a great running quad after almost 2 years. Changed the pilot jet from 12.5 to 17.5. A little adjusting and we are now good to go. Thank you very much. My son thanks you also. Can't believe how thrilled he is to have a normal running quad. I will be making a stop to the dealer with the old pilot jet in hand. He needs to know the product he sells a bit better I think. Again, THANKS!

 

You're welcome! Glad to be able to help. I guess the fact that I have 2 of these little machines (a 50, with an 80 engine in it now, and an 80) helps. ;-)

 

I'm beginning to think this may be the problem with my son's quad, a Raptor 80. I'm not familiar with how to change a pilot jet. Can you give me the Cliff Notes version? Do I have to take the carb off? Are these jets unique to each engine/carb, or are they a standard piece used on all carbs?

Thanks in advance for the answers!

SP

 

Yes, you must remove the carb, then disassemble the float chamber to get to the pilot. The jets are different for different models of carbs - you will have to find out what model carb it is. a competent bike shop/dealer should be able to help you out with getting the proper jet.

 

These carbs are notorious for not opening all the way too. Look for other threads here concerning mods to the raptor80 carb to get full effect. It will turn it into a rocket, not a sluggish brute as it comes from the factory. Raptor80racing has a lot of mods available as well. You also might remove the plastic restrictor piece that resides just in front of the air filter. It makes a big difference.
Lastly, Yamaha has all their parts manuals online, if you need to , refer to them for pics on where the restrictor is. I believe the picture you are looking for is actully the one that has the front plastic pieces on it. Don't aske me why they put it there, but it isn't on the carb page for sure...

 

Well i just switched my carburetor.. Now im not having full power.. When it starts theres no issue but when i go to full rev it cuts in an out. Go to pop it into gear it seems like to doesnt have half the power it did have. I was wondering if anyone had any suggestions that could help?

 

Take that new carb apart and make sure the jets are open. I know, you all ready did.. But still start there.