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450GN

Question about some mods... 04 yz450f

11 posts in this topic

hello just was wondering what everyone thought..

anyone have any comments to the rev cdi boxes they sell on ebay? do they help with anything or just give the bike a few more rpms before cutting out?

also i want to get a new pipe for the bike.. what is recommended? i would rather have more of a gain in the low end than the top but any gain would be good!... is a new head pipe recommended? i would like to get something that is of pretty good quality and doesnt cost 700$ like some i have seen

and another thing... does it seem like 4th gear is either really short or cuts out too early? my b uddy has an 04 crf450 and if we race straight line.. i will pull from start until i hit 4th and then he will catch up and pull ahead a little but they both top out at the same exact speed... well honda might be .5 mph faster but close enough... is there a good sprocket combo to give a lil more top speed and actually make 1st gear functional? it seems pretty short to me but i never really creep around the trails so kinda useless.. i just always use 2 to start in...

thanks for the replies in advance!

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dont know about rev box but i put just the dr.d slip-on on my 03 450. bottom and mid end had a huge power differnce without jetting, very responsive with or without silent insert

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thanks for the quick replies... i was wondering about jetting..

is it necessary or just one of those things you should do to to accomadate the new pipe? i would have no problem rejetting if the new pipe asks for it..

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you need to rejet when the weather dictates it anyhow, so testing and jetting for best performance is pretty much a given with a new pipe.

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hello just was wondering what everyone thought..

anyone have any comments to the rev cdi boxes they sell on ebay? do they help with anything or just give the bike a few more rpms before cutting out?

also i want to get a new pipe for the bike.. what is recommended? i would rather have more of a gain in the low end than the top but any gain would be good!... is a new head pipe recommended? i would like to get something that is of pretty good quality and doesnt cost 700$ like some i have seen

and another thing... does it seem like 4th gear is either really short or cuts out too early? my b uddy has an 04 crf450 and if we race straight line.. i will pull from start until i hit 4th and then he will catch up and pull ahead a little but they both top out at the same exact speed... well honda might be .5 mph faster but close enough... is there a good sprocket combo to give a lil more top speed and actually make 1st gear functional? it seems pretty short to me but i never really creep around the trails so kinda useless.. i just always use 2 to start in...

thanks for the replies in advance!

I do not have experience with CDI boxes

Consider a White Bros Alum Series race pipe 599.00 for all around performance as well as a JD Jetting kit to clean up the stock jetting. Also buy a ZipTy fuel screw - to adj

The 03 450 work well with a 47tooth rear sprocket or 48 stock

:naughty:

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Ga426- no offense, but why spend 600 bucks for the WB when you can get a TA for $320 ceramic coated? I really doubt that the WB pipe is $280 better. I do agree with you on the JD kit though, I would like to get one for my bike.

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check motosport outlet last time i checked they had white bros pro al for $350 delivered thats like half price factory yamaha runs them so i imagine they work

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Ga426- no offense, but why spend 600 bucks for the WB when you can get a TA for $320 ceramic coated? I really doubt that the WB pipe is $280 better. I do agree with you on the JD kit though, I would like to get one for my bike.

No offense taken Cowboyona426 - you know aftermarket pipes are like women and oil ...... some cost more than others and in the end ....................well that's another story! :naughty:

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I just installed the Dr. D slip-on on my 05 yzf450 and noticed a big increase in the bottom and mid of the powerband. I would suggest buying the one with the spark arrest option. This way you have the option of getting the quiet core. I didn't touch the jetting, just the fuel screw and it runs perfectly. I almost bought the White Bros. for $350 but you have no spark arrest option and they recommend using their packing which is $30. Dr. D pipes are made especially for Yamaha bikes. Dubach helped develop the yamaha four-strokes so I figured he knows each year and make of yamaha better than the next aftermarket pipe builder. That will probably be the only mod you will need for increased bottom and mid. Matt

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thanks for all the advice...

the thunder alley kinda looks odd with all the welds and pieces in plain view... but if it works :naughty:

seems like all the pipes mentioned are pretty good quality since i did a search and saw no complaints on them... can the thunder alley have a spark arrester installed? i didnt see that mentioned anywhere...

and also.. say i get either the Dr. D or t hunder alley... would you recommend the head pipe too or does just the slip on make the only difference?

what airfilter is recommended aswell? i have the stock one and have to clean it soon and would rather just throw in a new one if they help

and also i know this has been mentioned alot but what about the free mods! i did remove and cover the TPS sensor but what about the airbox mod? i have searched and didnt get a clear cut page on what to do... any help?

any other free mods or cheap mods?

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