NBSTUNTERZdave

ok, i got a gsx-r 750 and i just started hitting the bar. the bar is like 3 inches off the tail section. the bar is mounted to where the rear pegs bolt on and then supported to the bottom af the end of the subframe. now this thing is straight, i am positive of this cuz it will stand straight up by itself and i measured it 20 times.

well after it hit it a couple more times i noticed it was only hitting the left side of the skid plate. on video from a rear veiw, you can see the left side hit first cuz its twisting my whole tail section!!! now im no fat azz, i only weigh 160.

has anyone had this problem??????

thanks for the help,
dave

Brett256

If everything measures out straight on the bar then the surface you are scraping on, be it a parking lot or street, is probably not flat.

MikeM

Wne you first start scraping you usually hit on one side or the other. Keep practicing, you'll get straighter.

NBSTUNTERZdave

its sort of flat but when i do a high sit down it is straight compared to the ground, but as soon as i put my left foot on the back and do it again on the same stretch of ground you can definitly see its not straight, its like the subframe is twisting, putting the left side into the ground first...

skillz

not to get off the topic but 3 inches out seems to be a little too long , on a new gen. gixer the bar should be up against the tailight

Kyle_PBZ

Yeah, mine is 3 inches off the subframe and that's just where it needs to be.

As far as the subframe twisting you're right. It's from allyour weight being on the left peg. Stand behind the bike and twist the bar back and forth. You'll see that it twists really easy. It's no big deal. Just keep rocking it. And shorten that bar up.

twist~ROC

maybe because you are standing on the left rear peg, stablize the subframe bar that mount to the frame with some steel bars might help.

NBSTUNTERZdave

yeah, it may be a little bit out, but remember the gixxers tail section is shorter and the rear tire actually sticks out further without a bar. i just hit it for the first time on sunday and once i get comfortable and consistant, i'll shorten her up, trust me....

how should i strengthen the tail section so it wount twist up on me????

mikelocal12

put a level on your skid plate, that **** could be off. Try parking it on the bar and see if it will balance. if it doesn't that skid plate isn't right.

binder929rr

ya, way too long...almost all bikes the 12 bar has to be on the end of the tail or even closer. the bike will be unstable if you don't have it full 12 or more than 12. trust me, i just cut my bar shorter and it's much more stable.

and you can bolt something between the subframe bars to make it more stable. i jsut don't worry about it, you want it to give some anyways.

gsxrpeter1

hey on my gsxr I had a problem of the subframe allways coming loose when i'd twelve. You should realy put some lock tight on those bolts on the subframe.

Kyle_PBZ

Mine always did that too. I just went to Ace and got longer bolts and put nuts on the backside and tightened the s##t out of them. You will also probably end up breaking the lower mounts off the frame like I did. Your best bet is to find a good aluminum welder and have that gusseted up. Then take some 3/4"x1/8" aluminum strapping, again from the hardware store and run it down the sides of the lower subframe bars. Bolt if to your frame mount and a couple spots spread out down the bars. If you break something then you are hitting the bar way too hard!

nags

gixxers definetley have somewhat soft subframes.. you can see them move when you put your weight on the rear peg

Spark~R.O.C.

also... right where the left rear footpeg bracket mounts to the subframe bolt a piece of alluminum or steel vertical to the top of the subframe...that will help the subframe from twisting...Mark from MPZ has a solid piece of aluminum welded on to make it very solid

NBSTUNTERZdave

yeah, i allready did replace the bolts as said below this post. i saw geggv's frame, how he strengthened the frame for the lower subframe bolts. im working on that right now. im still not absolutly comfortable with scraping , but when i am the bar will be shortened.

and thanks to all of you with your help on this!!!!! thats what brothers are for...


dave

Kyle_PBZ

Well, I f-d up today. I was doing a standing still park, where you just stand with both feet on the ground and rip it up and park it. Well I ripped it up too hard and the back tire came off the ground and it landed hard on the top of the bar. I saved it but now it broke the top right side subframe mount/frame off. I cant win. Every time I think I get something fixed I f-up somthing else. Oh well, I'll just have it welded and strengthened up next week.

NBSTUNTERZdave

if i set the bike up on the bar, it will stay up straight, no problem

so if ima park it, what do i do, pull the clutch in as soon as the bar hits??? and stay on the brake???

binder929rr

set the bar ont eh ground and once you get a good drag then grab the clutch and let it slow itself down. don't use much brake if any at all once it's on the bar otherwise it'll fall back on 2 wheels.