drz 400 power dramas

hi to all the drz'ers im in desperate need of your knolledge on why my 400 feels guttless.ive got a 2001 drz 400 (pics are on my profile) its been converted to complete off roading which i love going :excuseme: on the wkends. the problem is my drz feels guttless ive just changed the rear sproket (47) and the front sproket (13 tooth) dont get me wrong its quicker now from what is was 14tooth on the front and a 34 on the rear to much top end for my liking, and its still dont scare the s***e out of me my understanding that 400 cc 4 strokes are supposed to be quite powerful and wheelie off the throttle but my bike dont. my mates dad said it could be the carb and i should uprate the float to a 40ml which mines only a 20 is that my main problem or is there some other things that could be making it guttless becuase this is doing my head in and all i want to do is :confused: please get back to me i would most appreitiate the advice and knowledge many thanks chris.

Which carb do you have? The fcr or cv? What is your jetting?

What exhaust is that? These bikes tend to be heavy on the front but with your gearing it should lift it fairly easily. My first guess is wrong jetting.

the exhuast is a two part exuast is a standard front pipe from the block and the second half is off a yz 400+ supposedly thats what my sargeant said but it says on the inside underneath the rear mud guard that its for on road use. my bike back fires(its like a bombs gone off)one of the blokes down my local bike track said my shouldnt back fire but ive heard its not uncommon for four strokes to back fire my mates dads 426f back fires like mine so i thought nothing of it and the carb thats on it is standard i think my sarge said it was on there when he got it so im guessing its a standard one. it does wheelie but i have to make the bike lift with the clutch and hitting jumps on it is scarey as you said its front heavy

Your gonna need to confirm the jetting of the bike before we can really help too much.

all we can do till then is guess. You do ahve to remember the DRZ is only a 35hp bike as standard. So it may feel a little guttless.

3x3 done?

Ok now everything is pointing to lean jetting: lack of power, the backfiring, etc. If I were you I'd take the carb off, ID it or show us a pic so we can ID it for you, and then see what jets are in there. Not sure what you mean by uprating the float?

Looking at the picts too it looks like it is an S (left hand bracket for pass pegs).

Need to look at doing the basics. 3X3, rejet, remove pair valve, etc. Poor thing is stopped up from the get go.

check the valve clearances sir !

shouldn't it be 53hp not 35?makes it sound like a john Deere.

You'll have to talk to Eddie to get 53 hp out of our DRZ. Stock is 34~ish, +/- 2. :confused:

shouldn't it be 53hp not 35?makes it sound like a john Deere.

:confused::excuseme: :excuseme: :sweden::crazy::p:lol::worthy: :worthy: :worthy::smirk::lol: :lol: :lol: :lol: :lol:

I'm just over 50hp. Go see what my engine is in my garage.

i'm really failing to see the need for more power in a full off road bike...hell I dont even use the 30 horses it has...we ride some pretty tight technical tough stuff and theres people on 125s making 450s seem like they are standing still. The fastest harescramble racer in missouri rides a wr250f. In a 7 mile track, watching from the sidelines, I watched him pass by my place 3 times before the 10th place person made it by twice....and there was a good 75 people on the track. I've ridden with him and its just insane...I think he just turned 20 too

Personally I like the 400 more then my 125 in the woods because of more bottom end...but more power would be a waste and might make riding more difficult. I say practice up with what you have and dont look at more power to make up for lack of skilz

i have a 55 horse power KLX 470 which i use for 95 % dirt use , i can assure you there are times when i have the throttle pinned ... charging up massive hills or along sweeping open trails . then it will crawl along tight sections only to go back to full noise again . i say yes .. have big power if your riding terrain can justify it .

i have a 55 horse power KLX 470 which i use for 95 % dirt use , i can assure you there are times when i have the throttle pinned ... charging up massive hills or along sweeping open trails . then it will crawl along tight sections only to go back to full noise again . i say yes .. have big power if your riding terrain can justify it .

Even if it doesn't it's still a lot of fun:busted:

I just sit in camp with dyno sheets and beer. Almost as fun :confused:

when I had my dirt DRZ, stock was enough for me....but I did nothing but trail/single track. I was faster on my XR250 honestly.

Street? No such thing as too much :excuseme:

i mean by the float cap on top of the carb and yea i need more power for the way i ride and i do go to tracks and i could do with a lil more pull. i saw my mates dad again today and he said i should change the float cap but im so tempted to get it skimmed and bored. plus im going to be doing enduro rallying wiv the army and that goes world wide so ive goto make sure im up for a fight as im not going to be beaten easily

On a DRZ no need to skim the head the base gasket thickness is the way to adjust compression. If I am correct and yours was an S you have the low compression version.

Look up all the common mods for an S and without too much money you can add 7 to 10 HP.

My S dyno'd at 40HP. (carb pipe and cams) Same as a KTM 450SX in fact I had a pony on him ....

yea it has got low compression actually now you mention it and its a fookin pig to kick over and i mean an absolute pig i cleand the spark plug up and that helped a little bit but its still a pain. ive got a couple weeks off in april so im going to strip her completly naked and try and get her sorted plus i want her to look the nuts coz shes going to be my little project bike

just got a new problem lads two of my valves have snapped ****ing typical and plus where theyve snaped theyve put some nice scratches and a lil dent in the top of the pistonand to make matters worse i think ma piston rings are on there way out becuase my bike is eating oil like no tomorrow plus ive been offerd a yzf 426 super motard for £1200 and its far from standard so im thinking of breaking my 400 and getting this yz as a daily and my weekend bitch any advice ?

you're looking at a full top end rebuild and replace the crank while you're at it because the rod may be bent. Search stores online for prices you can order. Stroke it while you're in there with a hotcranks stroker crank-actually, just copy the list of parts of the many members who have done the stroke, bore, valves, cams, pipes and carb mods/repairs/replacements and take it into a shop and order from their catalogues. While you're there, order a new set of fork boots or they'll be leaking in no time, get some springs and armour on it too-price high but you'll know what you've got.

You'll be sitting on 50hp+ and 290lbs with one of the best working suspensions out there and the reliability, toughness and user-friendliness to get you through.

Or drop 1500L on the wr and hope for the best. Your performance will be better than a stck drz, quite a bit less if you do the drz right.

the rings are the last of your worries.that motor was way worn out or the cam timing was off.

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