98 vmax 600 reed change, vforce 3 reeds

S

syc steve

New member
Joined
Jan 8, 2013
Messages
15
Age
47
Location
Sycamore IL
I just bought this 98 vmax 600 xt my first yamaha to be honest. I rode it on a trip up north and figured I would upgrade a few things. I bought the vforce 3 reeds and reassembled it. It seems to run worse now.
The reeds came with a spacer but there was not one on the stock reeds. Do I need to install the spacer?
It also backfires every once in a while even before I changed the reeds. Anyone had this problem with this sled. Plugs look good but doesnt smoke much. I'm thinking timing may be a little off.
 
Steve the back fire may possibly be due to dirty carbs... Yes it runs but it may be on the lean side. On the Red head chassis the triple cylinder motors benefit from reed spacers or reed stopper notch modifications to help the motor breathe better. Is it a triple or a twin cylinder motor? The stock reeds and cages are more than sufficient in these sleds as they flow well and Yamaha did their homework on these sleds. There may be a few mods or things for you to look at and adjust to help your sled run better.
 
Sxr700Bandit said:
Steve the back fire may possibly be due to dirty carbs... Yes it runs but it may be on the lean side. On the Red head chassis the triple cylinder motors benefit from reed spacers or reed stopper notch modifications to help the motor breathe better. Is it a triple or a twin cylinder motor? The stock reeds and cages are more than sufficient in these sleds as they flow well and Yamaha did their homework on these sleds. There may be a few mods or things for you to look at and adjust to help your sled run better.
Click to expand...

It's a twin. I thoroughly cleaned the carbs when I had them off too. It doesn't go bang just like a poof or light pop. Thought it might be loading up too. I might as well leave the reeds on now. It has 5056 mi on it just figured they might be worn out. Stock peddals would have been cheeper.
 
When running worse, do you mean at most or all throttle positions or particularly on the low end?? Help diagnose please.

You may want to check your choke plungers as they may be slightly hanging up and causing a rich condition. What kind of spacer?? like to space the reed block back or on the reeds themselves? What kind of gaskets were there in pace paper or metal? Please explain. Also are the carbs seated nicely in the carb boots and is the boost bottle and clamps on snugly??? I am looking for air leaks.
 
Sxr700Bandit said:
When running worse, do you mean at most or all throttle positions or particularly on the low end?? Help diagnose please.

You may want to check your choke plungers as they may be slightly hanging up and causing a rich condition. What kind of spacer?? like to space the reed block back or on the reeds themselves? What kind of gaskets were there in pace paper or metal? Please explain. Also are the carbs seated nicely in the carb boots and is the boost bottle and clamps on snugly??? I am looking for air leaks.
Click to expand...

I only was able to run it in the garage and make a lap around the house, we have no snow here. Mostly low end, little boggy.
The spacer is a reed block that came with the reed cages to set them farther away from the carbs about 1/4''. The gaskets are paper. The carbs a bottomed out in the boots and the bottle and clamps are tight. The plugs look brown although I have not been able to run it wide open long enough. I'll have to take it back apart tonight and check the chokes.
 
Did you check to see how the carbs are adjusted? Throttle valve at proper height at idle, fuel screw 1.5 turns out, idle set to 1500rpm. I had this problem with my 97 600 (same engine) after adjusting my carbs its like a new engine!
 
brade07 said:
Did you check to see how the carbs are adjusted? Throttle valve at proper height at idle, fuel screw 1.5 turns out, idle set to 1500rpm. I had this problem with my 97 600 (same engine) after adjusting my carbs its like a new engine!
Click to expand...

No I didn't yet. I only see one screw on the float bowl. Looks like the fuel screws are not existant on these carbs.
 
A couple of bucks said:
Here are a few of our members that live in Sycamore.
Chris...http://www.totallyamaha.net/forums/member.php?u=3755
Steve...http://www.totallyamaha.net/forums/member.php?userid=11319
Send em a private message.
Click to expand...

Thanks. I think that guy chris sells parts and works on Yamahas at his house a few blocks from me. I bought a skid for the suspenion from him after I got this sled. Thought about calling him but wasen't sure if he would be willing to help sense he charges to fix sleds.
 
It would be nice if I could bring it out in the field and do some laps to get a better idea how it's running. I don't think cold mud would do it any good and it's to warm to hoist up the rear and rev it up to get a good reading on the plugs. Putting a 2002 A.C ZR600 back together too.
Theres a huge snow storm going north of us again this weekend. Driving me nuts.
 
Last edited:
dblshock said:
..and nothing but sun on the 10 day forecast.
Click to expand...

Guess we should be happy we put on 200 mi in Newglarus and south west Maddison new years weekend. They have some nice trails but need more gas stops. I think i got the wife hooked. Not sure if that good or bad. She loves atving and said she isn't shure what she likes more LOL.
Should have had more spotted cow good stuff.
 
Last edited:
I put the vforce 3 reeds on a 97 MM600 twin and yes you need the spacers. Mine runs great. What jets are you running?
 
I would say you need to instal those spacers. the v force reeds might be blockin the port causing it to run bad .dont know for sure but it seems reasonable!
 
yammy said:
I would say you need to instal those spacers. the v force reeds might be blockin the port causing it to run bad .dont know for sure but it seems reasonable!
Click to expand...

The local power sport shop guy told me the spacer is more for top end power and low end without it.
I was trying to locate the piolet jet on these carbs but dont see any. Only screws I see are on the side of the float bowl close to the bottom?
 
mtnmaxman600 said:
I put the vforce 3 reeds on a 97 MM600 twin and yes you need the spacers. Mine runs great. What jets are you running?
Click to expand...

I forgot to look when I had it apart the first time. I have not taken it back apart yet. Ill post it when I do.
 
I believe the reed hits the housing and will not open fully without the spacer. Also the pilot jet is under the float bowl on the carb the screw you are referring to is the drain for the float bowl. The air mixture screw that is adjustable from the outside of the carb is loacted on the bottom side of the main carb body and is almost impossible to adjust with the sled air box on the machine. You should have the screw backed out 1 and 1/2 turns at a good starting point.
 
You must log in or register to reply here.


Back
Top