uchi

had the bike out tonite, it was cold out, around 46 degrees or so, and i was finding anytime i rolled off the throttle at over 6000 rpm or maybe even a bit higher she'd pop, and it wasnt like a detonation kind of pop, more like a i just shot a fireball and heres the proof kind of pop and then the bike would be a little less responsive for a few seconds, maybe flooding the plugs? were opening the carbs again soon to put the 48 in thats finally arrived and when the carbs were adjusted it was fairly cold outside and we figured she'd get richer with a bit of warmer temp. actually im finding that this started happening more after adjusting the tps, not sure if that makes sense or not

residentg

Have you removed or disabled the PAIR valves?

uchi

Yup pair stuff is gone. I'm pretty sure its rich. Judging by how much gas I burnt through tonite it better be rich. Lol

RCVTR

Sounds more like it's lean to me. So lean that it doesn't fire, when the throttle is closed. This dumps a bunch of unburned fuel and air into the exhaust system.

When it does fire, it lights it off.

nath981

what did you set your tps at? what color are the pipes when you look at them from the rear. preferably with sunlight? try pulling you choke out and see if it happens.

uchi

thats possible. i didnt get to check the pipes, i do find that the bike doesnt like cruising in 6th gear, gets a little chuggy, and 5th at times aswell. im gonna check the plug on it tomorrow or later tonite if the motivation sets in, i just didnt want to burn my hand checking it when i got home.

tps is at 588, i havent had time the yank the box off again and to bend the tab and to set it lower. it was at 818, so i thought that maybe setting it lower would have caused it to richen up a bit, thought the pops might have been from too much fuel, could be lean too as mentioned above. see what story the plug tells

uchi

also i was thinking it was rich because its happening at 6000 and above, below that its fine and its only when im hanging out there for more than a few seconds and i roll off the throttle and then the bike gets un responsive almost as if the plugs been fouled

nath981

yeah set the tps 490-500, raise the needle. what jets, air mix? Steve29s wwas acting similar and we got his to stop by messin with above three things.

uchi

i cvant remember what the carbs are set like off the top of my head. ive got that drilled 45 in there and my 48 showed up. i bought a jet kit from here from a guy who bought it used from another guy and along the line it lost the 188 jets and the 48's. so my 48s are here now just need to get them in, the needles been shimmed so its likely gonna have to get un shimmed. i noticed the bike would get a little chuggy at cruising rpms and my buddy who was behind me on his vfr said he could hear it chugging and when id roll into the throttle a good bit it would blow black smoke for a second and then pick up and go. so either its running rich as im suspecting because of the tps adjustment and the already shimmed needle.

on a positive note he said my bike pulls like a raped ape, his vfr800 has a leo vince exhaust and -1 sprocket and he said he cant hang with me at all. said he'd need to go up one in the rear and drop about 75 pounds, lol. so thats nice cause last year when he had the exhaust we were dead even everytime.

quick tps related question, i dont wanna start bending tabs to **** and from the writeups i havent seen what you guys are doing to bend the tabs, do you happen to have some pictures or a better way of doing it?

nath981

bending tabs: all you need to do is take a needle nose or small pliars, or channel locks and bend the rear/downward tab a little(bend outward,toward the rear, a little to let the tps move a little more counterclockwise) and that's it. No biggie. Simple. as far as your carbs, the needle probably isn't shimmed if it's an aftermarket needle. It has slots or groves with a clip holding it and you can move the clip up or down to suit. You may as well get used to goin in and out of there til you get it right, and I ain't talking about your girlfriend either. lol

uchi

damn i was just getting used to that, lol

alright ill get in there tomorrow i think, i need to check the damn front plug anyway so might aswell make an evening out of it

the needle is from the dynojet kit and it was still rnning lean so it had been shimmed. i talked to the fella from factory pro and along with what i learned here the bike wont run smooth at lower rpms with the tps being adjusted. the guy said any other bike and shimming the needle would resolve the issues i had but for whatever reason with out big carbs it just doesnt work. lets just hope when we get back in there its not gonna end up being a day long ordeal. im hopeing the bike is close enough so that when we change to the 48 itll clear out most of the issues weve been having, then remove the shims and by some form of bike magic it fixes itself, lol

nath981

wishin for magic! hahahaha. sounds like you gotta a bunch of hokus pokus goin on in there already. you'll get it right. I have faith in ya. lol

uchi

Lol. Well I'm sure I will. I just don't want to spend too much damn time doing it. Lol

nath981

maybe you'll get lucky, but that's not how it usually works for me. haha

uchi

Alright. Well its definatly not running rich. Not the front cylinder anyway. I yanked the plug. It looks decent. A little on the lean side but not super lean like I thought it might had been. So unless the rear plug is the exact opposite of this, which it could be, I don't think I'm too far off from the bike running decent.

nath981

looks pretty good. Like you said maybe a little lean dependent on how hard the bike was run before you shut it off. But definitively close to right.

uchi

I tried to run it hard and shut if off and coast her into my driveway. Do I have to yank the tank to get to the rear plug? I wanna check it to make sure both cylinders are running close to eachother.

VTRsurfer

Take the front tank bolts out then remove the rear bolt and use the u-shaped tool in the tool kit (if you have it) to prop the rear of the tank up. You can reach the rear plug from there no problem. No need to disconnect any hoses.

Little_Horse

also plugs on the superhawk are hard to fowl by design and gas nowadys doesn't tell the same story it used to. Often times in my experience the hawk will miss fire if mix is off very much either way and when things don't fire the gas goes into the exhaust and pops so backfiring could be either lean or rich. Don't assume that because of an aftermarket exhaust that you need to go even more rich. On Springbubba's hawk we thought it was lean missing so we richened it and it made it worse so interestingly he is running leaner the stock now and he as aftermarket pipes.

inderocker

Pull the choke during the same conditions, if it runs better your lean. Ofcourse, don't go riding around with the choke pulled for too long, that's a good way to put a hole in a piston.

uchi

i thtink think running rich would do anything but wash the rings out and contaminate the oil and eventually lead to broken down oil and what not, i know lean can burn a hole, seen it in a buddys car

ill try the choke thing next time im on the bike.

i was wondering what the hell that weird u shaped thing was, i was looking at it the other day thought someone might have tossed it in there as a joke somewhere down the line of owners, lol.

thanks for the info ill try to get out on the bike today and see if i can get some more info

nath981

uch, get over that pulling the tank thing. Use a small ratchet strap to lift the front of the tank to about 45 deg. There's a pic of this somewhere on here and it's a great time saver and facilitator, and it's easy and stable. Better to not have your tank topped off for obvious reasons. You can pull the filter box carbs, sync carbs whatever and we got the rear plug out of steve29s with the right socket/extension, but it is a little tight.

uchi

I've had it up a lot. I've got a 2x4 I've measured and cut to use as a prop rod. Lol. Even says bike prop rod. Do not burn. Haha. Ill get that plug oiut tomorrow

nath981

you said yank the tank so i thought yank the tank. get youself a little ratchet strap. it's unobstrusive and stable and cool lookin, not like a clumsy, clunky lookin 2 by. what's wrong with you? hahaha

seriuously, i think you're better off changing needle setting, air mix, tps and enjoy the trial and err method.

uchi

Yeah its all getting adjusted. I just wanted to know for myself so I removed the plug it'll be sorted out shortly. Prime riding season is coming

VTRsurfer

That's funny...I still have a piece of 2x8 in my garage with "BMW stand" lettered on it. My old '83 R100RS had a "ride off" center stand. You could just click it into gear and ride off the center stand, but you couldn't pull a wheel. So I'd put that chunk of 2x8 under the center stand to get the rear wheel off the ground.

uchi

haha thats wicked. improvised anything is usually good for a laugh, especially when its hillbilly improvised like the car i saw on a home made set of ramps made of cinder blocks

uchi

Ok. So here's what I discovered. Now its been cool on every ride I've been on so the bike hasn't gotten past 80 degrees. 104 its as hot as it'll get. So usually its around 96 or 97. Anyways. 4000 rpm 6th gear it would start to chug a bit. I pull the choke a little and she clears right up. But when it hit about 102 degrees at a red light it was feeling chuggy and when I pulled the choke it got worse. Although when its at a cooler temp its idleing fine and is responsive. So yeah I'm not sure where to start with it.

steve29

Are the emulsion tubes correct? They are different in each carb. I understand that having them wrong can cause issues similar to yours. Also you may want to put your needle on the 5th clip from the top and turn your pilot screws to 2.5 turns out. 2.5 is what dynojet recommends snd I found it works well that way. However, ymmv as they say. Good luck

residentg

From the Factory Pro site, see the difference in the location of the holes. Also, hopefully the DynoJet instructions are attached to this. My bike has a mystery Jet Kit in it from the PO. It is definately running rich. I just ordered a Factory Pro-1.1 kit, and BMC filter to replace the K&N, sometimes it is best to start from scratch. Hopefully I wont have to fill in any drilled holes. JB