Bandit Alley
MODEL SPECIFIC => SUZUKI BANDIT 250 & 400 => Topic started by: andrewsw on September 08, 2006, 09:32:45 PM
-
I got a chance to do some top end runs and want to get some comparisons from others before I start swapping jets :wink:
I've a '93 B4 with a Yosh full exhaust, k&n filter, stock airbox with snorkel removed, 97.5 mains (not 100 as I thought previously). This is a fully naked bike with my 6'1" 200#'s tucked in as tight as I could get. Everything else is in decent shape: valves recently (300 miles) adjusted, sync is pretty close but a little off from some recent carb work, etc.
So wide open on a flat road with not much wind, but a very hot 94 F, I hit 108 indicated on successive runs with just a little vvvveeeerrrryyyyy slow pull left like it might have gone to 110 absolute top. Up above 100 (about 10k on the revs) it was just about out of pull and really crawled its way up from that point on.
I suspect I should be able to get more top than that. Am I right on this? or should I be happy? I have a few mains floating around (102.5 and 105, but no 100's) that I could try.
I have no indication that I am running lean (popping for example) but haven't done a throttle chop to check the plugs and see for sure.
-
I have had 128ish indicated on my '92 B4. But I do have a fairing, and i'm not quite 6'1"! lol
I'd say that 108 is quite respectable, but you should be able to get a bit more out of it.
I dont know what you are talking about when you talk about 100 mains, so i'll just ignore that bit! lol
-
how many wires to the plugs on the cdi the small plug mainly?
-
Only once did I do it, but I was able to hit ~115mph with those carbs. I weigh ~160, so your 110 sounds to be about right.
-
You should be able to go faster then that! I've had an indicated 200+ kph (125mph)... mind you i'm pretty much weightless (5'11", 135 lbs)! :lol: ...and the speedo is optimistic.
-
You should be able to go faster then that! I've had an indicated 200+ kph (125mph)... mind you i'm pretty much weightless (5'11", 135 lbs)! Laughing ...and the speedo is optimistic.
+1!
Yesterday i had a chance to whop the throttle, and got a constant 190kmh, and this was with a pillion hunched up behind me.
i'm guessing our weights combined around the 120kg's so equals 240pounds?
-
[quotehow many wires to the plugs on the cdi the small plug mainly?[/quote]
not sure, but I'll check and report back. you're thinking of a limiter I assume?
I'm pretty sure it was a horsepower issue. I think my power is peaking around 10k and falling off rapidly after that. I had similar behavior in 5th gear where after about 10k, its pull really dropped dramatically, and I would shift into six which dropped the revs back into the power and got me up over 100. So something is going on with the power band there.
I'll report back on the CDI.
-
Krautwagen, I agree that if you were getting 115 at your weight, it reasonable that I might only get 110. And of course, there are a lot of other factors that I haven't looked into that could affect things as well -- namely engine wear. If you throw in the altitude difference, which is probably not enough to need rejetting, but is still probably a factor in peak horsepower, then it really makes sense.
I still think it should be pulling better at that point though. Did you experiment with the main jets at all? the guys at FP seemed to think its a borderline case for the main jet with the k&n etc.
I've gotta do a throttle chop (ugh, pulling hot plugs is scary) and see what she's doing up there.
-
With mine I hit over 220 kph and start hitting the rev limiter and yes i have stock gearing before anyone asks. And I'm a heavy weight 210 without my leathers on. Yours Is also a 93 and they have a lot tamer valve timing so that might be all she has
-
Yours Is also a 93 and they have a lot tamer valve timing so that might be all she has
huh. thats interesting to learn. that probably explains the difference in the valve clearances too. is it as simple as putting the older cams in? or is there more to it than that? not something I'd likely do, but I'm curious.
A
-
Yes Jay maybe able to hook you up with some hotter cams
-
You should be able to go faster then that! I've had an indicated 200+ kph (125mph)... mind you i'm pretty much weightless (5'11", 135 lbs)! :lol: ...and the speedo is optimistic.
That's probably not helping with your insurance...
:lol:
-
you bike is a 93 ? lmao check the cdi wires
-
That's probably not helping with your insurance...
:lol:
It's not my fault I'm skinny. :lol:
Seriously, don't get caught doing double the limit on the street. And if you do don't stop.
-
I hate CDI
It sounds wierd that the power drops dramatically after 10k revs. And that when you go up a gear you get into the power. My engine* pulls well till about 8k, and then it pulls like a train, ans then at about 10k it's off like a rocket! Sounds like yours is the exact opposite. And when i want to get into the power (for overtaking or whatever) I drop a gear, i dont go up a gear.
*This was before it blew up. :duh:
This makes me agree with Jay in thinking that it must be the CDI. The CDI controls how the engine behaves. (After getting a new engine, i discovered that my CDI is phucked and the engine wont rev at all!)
Check the wires coming out of the CDI, and check them where they go into the coils / engine (wherever the hell they go!). If these are okay, there is a company (at least one i know of in the UK) who test them for about £30, and if they find a fault they can fix it for £90-120. Alternatively, you could buy one online, like on eBay, or even on here, I have seen a couple advertised lately. I bought one off ebay last week for £40, but I seen one at £250, so there is a huge price range. The last option is that you could fix it yourself. There are a few posts that detail how to do this, but they are dotted all over te place and a bit vague and confusing. This is a post i made with all of the information I found about DIY CDI repair, and a few peoples helpful comments. If you'd be interested in fixing it yourself, take a look:
http://forums.banditalley.net/viewtopic.php?p=51122&highlight=#51122
That is all assuming that it is your CDI thats busted. If thats not the problem, then I can't help! Sorry!
-
you bike is a 93 ? lmao check the cdi wires
yep its s '93. cdi has 7 wires: 3 to the small plug and 4 to the large plug.
does that mean its limited?
-
Andrew - all the fun should be above 10k. IMHO, with that set up you're way lean on top. With my last configuration, I was pulling hard to the rev limiter. I'm lighter than you at ~162 but I think you should easily get more out of it. I may have actually been a little rich with 110s but I'll bet you'd see a big improvement with 102.5 or 105. (You have FP needles, right?)
-
PitterB4, yeah, I'm starting to think the same thing. My old '91 pulled better too. not sure what it had for mains, but it didn't have the k&n/snorkel removal and pulled better. Of course, I wasn't 200#'s.... but I also wasn't much less than 190#. And yes, I have FP needles. Will have to try the larger jets.... maybe tomorrow. :grin:
Like I've said before, I haven't done any throttle chops, anyone else find that a reliable method for checking main jet size? or is top speed just as good an indicator?
Oh, it does pull fine over 10k in the lower gears, but then in the lower gears, its harder to tell how much is engine pull and how much is gearing. the power drop shows in the taller gears above 10k. I'm gonna have to do some more "scientific" testing. My top end runs were on a ride with a 1200 bandit and a cbr929 in front of me... more of a frantic attempt to keep up than a really good methodical test. It was tough in the straights, but gotta love than bandit when the road starts to curl up on itself. Those power junkies can't handle for crap :monkeymoon: when it gets a little twisty :motorsmile:
nothing like watching the big boys pull away and then start panicking and looking over their shoulders when I'm all over the butts in the corners weeeeeee.....
-
i think there is something definatley fishy with the 3 wire cdi's i had one and it def had the same problems as you once it got so high it just didnt make no power seemed flat when it should have been pulling hard still everything i did just improved everything under that spot never helped it pull the rest of the way till i swaped out wiring harnesses and cdi boxes so now i no longer have that issue mine pulles to 14500. So anyone wanna buy a year old 93 cdi box. I think the bike is in need of a mmax derestrictor if they make one for the bandit.
cheers
Jay
-
huh. I looked at the wiring diagram for the 1993, but itsonly available in the low-res manual and is essentially unreadable. Did you try just disconnecting the one extra wire? (yellow/green, right?).
Anybody got a readable copy of the '93 wiring diagram they can send me?
I can't imagine they completely redesigned the CDI, just enabled some functionallity that was always there. so then it should be fairly easy to disable that "feature".
whats a mmax derestrictor?
-
there is a posh derestrictor, mmax and others that wire due to the harness has power to it something low voltage but follow that wire it is hooked to your gear indicator on the left sides by your foot i think the bike is speed restricted, anytime your cdi is conected to the gears its bad news. Chris H has a derestrictor on his contact him if you can on this board and ask him all i know is you cant unplug it it does nothing pluged in or not still the same. So if you wish unplug it yourself and go ride it. other thing that sucks is this cdi doesnt work in my bike now that ive changed the wireharness over but the 7 cdi's that i had that i thought i had to fix all work now , so you tell me but best bet is to get ahold of chris Hand ask him about his something to do with that wires to ground with a diode in between. cheers sorry i couldnt be more help i went about it the hard way.
Jay
-
well, I've got a green w/ yellow wire running into my harness at the back by the cdi, the next green w/ yellow coming out of it actually runs to the oil pressure sending unit. So, that's not the right one. it changes color somewhere in the wiring harness (ugh). So I'll have to cut it or rip apart the harness and see what I can find.
How annoying is this, why in the world would they put this kind of limiting on such a small bike?
anyway, off to change jets and make sure that's not the issue.
A
-
okay here's an interesting bit that I found.
http://www.visordown.com/forums/archive/index.php/t-81782.html
They talk about a sensor in the speedo that might be causing the restricting and you can basically modify the speedo to eliminate the restriction.
anyone got insight on this?
A
-
You DO NOT have a restricted bike so stop chasing after rainbows! Get your jetting right first your way too lean with the combination you have just as Rob has stated!!! If the bike runs I can bet the ignitor is fine
-
While you should ideally only change one thing at a time, I'd also make sure your needles are on the middle clip position when you go to the bigger main. I am too lazy to go look at your older posts but I seem to remember that you'd raised the them.
-
At this point Rob is the carb Ninja. I don't know of anyone who dicked around more with them besides Jay.
-Randy
-
You DO NOT have a restricted bike so stop chasing after rainbows! Get your jetting right first your way too lean with the combination you have just as Rob has stated!!! If the bike runs I can bet the ignitor is fine
Ok so why is there some that are and some that arent , some that have 2 wires and some that have 3 , some that are speed resticted How about Chris H's bike it was restricted electonically?
-
BECAUSE no bikes that were sold in north america were RESTRICTED. If you think the bandit is bad for different igniters the older GSXR 750 and 1100 are a nightmare!!!!!
-
i have a totaly stock bandit its a gsf400vp i have got it up to 125mph (and have the speeding ticket to prove it lol) personaly for road use why you would need anything more than that is beyond me
-
cool! I started a flame war! :duh:
okay, Thief400, just so you know, I am pursuing the jetting and agree that I was/am too lean up top. I was merely attempting to educate myself. (something I do lots of :grin:).
I've subsequently jumped from a 97.5 to a 102.5 main and have no problems. I will go up to a 105 today and see what that does.
However... it has not yet solved the brickwall that hits over 100. Now, I didn't get to REALLY test it as there were cops lurking around and I was forced to less than ideal testing grounds. But I watched it pull like a train in all gears up to redline but 5th & 6th gear it basically dies at about 10k (somewhere around 100mph) and pulls much more slowly up to around 105 which was all the room I had on that road. Maybe that is just the current shape of the power curve and it only really shows in those taller gears because that's where the horspower is no longer sufficient.
PitterB4, yeah, I definitely need to raise that needle another notch. I had pulled it up from 1 to 2 already when I fixed the worn emulsion tubes/slide carriers. It still seems a little dry right in the needle range.
wyntrblue, I agree. I don't need anything over 90, frankly, but am in pursuit of a properly setup bike, even if I don't use it fully most of the time. This whole issue came up cause I went on a ride with some big boys and found my top end on a nice long straight while I was riding in the middle of the pack.
to all of you: :thanks:
-
Did the bigger main help at all?
Another thought... are you running stock gearing? Maybe the bike is geared lower and not capable of faster speeds. Like I said... just a thought.
-
the bigger main didn't seem to help, but I didn't have the best testing conditions, so we'll see. It did not, however hurt the situation and it seemed to pull stronger off the main in general.
huh. gearing. good point. I keep finding things that have been modded on this bike that the PO didn't know about. Worth a look. In fact, now that I think about it, that is a very real possibility. I was thinking I've been faster through the gears but not going all that fast. I'll check it too.
-
the carbs are the 32 or 33 mm if they are 32's and the 93 cams thats all your going to get. another thing is your tach might be out of wack. mine is reading almost 1800 rpm to high
-
yeah, 32mm carbs and 93 cams. well, that's fine with me really. I'm just looking to get it do what it will do withing reason and without serious mods.
for now.
so I can assume that although it might need a still larger jet (Like a 105 I think) that will only improve small amount at best up at that level? What do those cams do that the older ones don't? or vice versa I guess...
-
With all due respect, Chris - that's BS. He's basically running the same set up as I was - 93 with 32mm carbs, full race system, modded airbox, K&N... and mine pulled VERY well past 10K and 100MPH. If bigger mains you got >10k improvements in lower gears, keep going. If you think about it, that makes sense - the higher gear you're in, the faster you're going, the more air is pushing through to the combustion chamber, the more fuel it needs. Like I said, keep going. Maybe de-snorkled, you have to go a lot bigger. I never had the guts to pull the snorkle. Tuning is a pain.
-
I still have doubts about the advantage of pulling the snorkel. seems to me that the snorkel, while it restricts the opening somewhat, probably also has a bit of a velocity stack effect. And its also got a nice radiused edge that should allow for smooth airflow. With the snorkel pulled, you just have a hole. I would think, especially at higher revs with consequent higher airflow, you might get some induced turbulence at the edge that could actually restrict air flow. But I am no rocket scientist :wink:
Tuning is fun, IMO, as its another excuse to go ride :grin:
So I've got so many conflicting ideas now its ridiculous. I may or may not be limited due to the 7 wire CDI. I may have reduced performance due to 93 cams. I may simply not be jetted right.
I'm pretty sure about the latter -- the 102.5 helped, but didn't solve the top-end run issue. I'm going to try the 105 and see what that does. I'm pretty confidant that I've got some room to go in the jetting, and PitterB4, if you were running a little rich with 110s, then my 105 is probably right on. If that doesn't improve the top-end situation, then I'll play around with cutting that 7th CDI wire and see what that does. waiting to hear back from ChrisH (?) about his CDI mods. I can tell you I'll NOT be into swapping cams anytime soon... But I will be checking things like compression, cam timing (maybe its jumped a tooth?) and other stuff like that that may affect it.
Regardless, its clear that I'm not getting the top-end I should and will keep plugging away at it.
Oh, and the sprockets are stock, so that's not an issue.
There is one other issue that may be a factor. My speedo could be out of whack. One of the guys following me the other day called it 120. I pointed out that he was passing me... I can't imagine our speedos would differ THAT much anyway. And he was passing me pretty good, so I think he was just being nice to me :lol:
-
The 93 is different in many ways. It does have different cams. It also has different timing, different gearing and takes a plug one step cooler. I don't think it's de-tuned, it's just differently tuned.
I've heard that explanation about the snorkel before. That's one of the reasons I suggested in another thread that you spend $20 on a new box lid. I don't have any personal experience with it to know for sure, tho.
My bike being a little rich on top was a guess. I never got it 100% perfect before I gave up and took it back to near-stock to sell it. Up top, it was a real monster through all the gears. Again, the wild card as compared to mine is the snorkle.
-
yeah I had no snorkel to start with. yee haw...
A
-
So I've gone to a 105 main and position 3 on the needles. Running pretty good though its a touch rich on the needles I think. Doesn't stumble, but it gets a little soggy cruising with a steady throttle. might drop it to 2.5. Didn't get a real top-end run again, but it was pulling pretty hard up above 90. we'll see.
edit: that'll be a float adjustment for the sogginess, not a needle adjustment. That info from factory pro is great for this stuff....
-
just to wrap up this thread in case anyone's looking.
mid range sogginess was worn emulsion tubes. Also the slide carriers were worn which was probably accelerating the emulsion tube wear. Replaced both of those (luckily the ones in my extra carbs were good!). So that helped the mid range, just off-idle cruise a lot. Also, I raised the floats (leaner) by 1mm to 16mm, which is opposite of what a lot of people do, but it helped as well. Roll-on and cruising is now great.
Main jet is still at 105, needle at 3 and it seems pretty good. I haven't had opportunity to do a real top end run again, but todays ride (real twisty :grin:) I did get it up to 100 a couple times with it pulling real good still, so I think its probably right, or close enough.
So thanks to all who helped get my girl rolling right! :thanks: and I owe you some :beers: