excallibur101
Pro
I need some advice if anyone could help me. I own a 2005 Yamaha Warrior and have plans to remove and clean the carbs as it needs due to slight misfire at idle.I believe its my pilots.During the process I plan on installing two TPI valves on the air box as well as increasing my pilot and main jets to compensate for the air increase,nothing drastic as the sled is stock.Any information on what sizes I should increase to and any other info would be appreciated.
rxrider
Jan-Ove Pedersen
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Are you opening up the box a lot I would go with 165 mains. Make a search this have been covered beore. Make a search for TPI
excallibur101
Pro
I plan on making the holes the size of the openings of the valve window ,nothing drastic,only two valves to gain some performance without offsetting the air/fuel ratio by over or under jetting.
Len Todd
TY 4 Stroke God
Where do you put two of them so that all 4 carbs are still balanced?
excallibur101
Pro
TPI valves
I plan on two valves because I believe 4 valves would be somewhat overkill allowing to much air to enter the stock airbox as it does need a certain amount of restriction to attain proper vacuum for the carbs to draw fuel effectively.The airbox is an open chamber and is not chambered individually to require seperate valves to require 4 valves as the stock box has one opening supplying air to all 4 carbs to run the engine .My intentions are to gain a few extra horses with the right amount of added air with the proper jetting size increase to do away with the factory lean condition they are set for emmission purposes as well as a greater chance of have the jets clog .Any info you feel I should know would be helpful,I am open to advice.
I plan on two valves because I believe 4 valves would be somewhat overkill allowing to much air to enter the stock airbox as it does need a certain amount of restriction to attain proper vacuum for the carbs to draw fuel effectively.The airbox is an open chamber and is not chambered individually to require seperate valves to require 4 valves as the stock box has one opening supplying air to all 4 carbs to run the engine .My intentions are to gain a few extra horses with the right amount of added air with the proper jetting size increase to do away with the factory lean condition they are set for emmission purposes as well as a greater chance of have the jets clog .Any info you feel I should know would be helpful,I am open to advice.
Len Todd
TY 4 Stroke God
The only reason I asked my question is; we have had a few posts of people planning to add the valves. Seldom have I seen the results posted. I have seen a couple threads where they end up leaving them closed. I just have not seen posts that show any definite improvement by adding TPIs, or even someone that is committed to a position that the TPIs made a significant improvement.
I do know that if the airbox is even just slightly NOT sealed up, the sled runs crappy. This suggests to me that changing them may not be an improvement. But, if you are willing to tackle rejectting, then maybe that is an answer to the crappy running problem.
In regards to my question, I would think that you would want to balance the added air to ensure that all the carbs will get it evenly.
But then, I have not tried it myself. I am just watching the posts. But, ... that is not to say that I may have missed a few on this topic that were successful. Again, I have just not seen any posts that report significant success. I guess worst case you could always leave them closed, if things do not work out.
I do know that if the airbox is even just slightly NOT sealed up, the sled runs crappy. This suggests to me that changing them may not be an improvement. But, if you are willing to tackle rejectting, then maybe that is an answer to the crappy running problem.
In regards to my question, I would think that you would want to balance the added air to ensure that all the carbs will get it evenly.
But then, I have not tried it myself. I am just watching the posts. But, ... that is not to say that I may have missed a few on this topic that were successful. Again, I have just not seen any posts that report significant success. I guess worst case you could always leave them closed, if things do not work out.
rxrider
Jan-Ove Pedersen
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- 2014 Phazer XTX, 2013 Phazer RTX, 2008 Apex RTX, 2007 Warrior, 2006 Attak
Good point Len 
excallibur101 - The airbox is not a restrictor, it's resonator. The vacuum that sucks fuel off the main jets is created inside the engine (engine does the breathing) the vacuum created by the engine sucks air thru the carbs venturi creating the venturi effect which sucks fuel from the mains and other jets as well.
Install all TPI's as the install guide tells you to, they were designed using all of them, there should also be some jetting baseline coming with the kit. A friend of mine ran the TPI's and if I remember it correctly he ran 165 mains, his sled ran pretty good for a stocker
Good luck with the new power, remember to adjuct clutching accordingly.
BTW - would you mind adding your location in your user profile, it's a site requirement.
rxrider
TY Management
excallibur101 - The airbox is not a restrictor, it's resonator. The vacuum that sucks fuel off the main jets is created inside the engine (engine does the breathing) the vacuum created by the engine sucks air thru the carbs venturi creating the venturi effect which sucks fuel from the mains and other jets as well.
Install all TPI's as the install guide tells you to, they were designed using all of them, there should also be some jetting baseline coming with the kit. A friend of mine ran the TPI's and if I remember it correctly he ran 165 mains, his sled ran pretty good for a stocker
Good luck with the new power, remember to adjuct clutching accordingly.
BTW - would you mind adding your location in your user profile, it's a site requirement.
rxrider
TY Management
