My pipes are purple ...

[Akira7R]

...yes they are .
That means my bike is runing lean or rich ?
To much fuel or not enough ?
Somebody help me please !!!

[scott_tiller]

When you say your pipes are purple, do you mean your header pipes are purple?

Its normal for pipes to discolor starting at the headers all the way to the can. This is due to the heating up of material (stainless steel, nickel plated or titanium). Some bikes run hotter than others, so some discolor more than others.

If you think you are running too rich (too much gas) or too lean (not enough gas) check your spark plugs.

Trina

[Anonymous]

:imwithstupid:

I believe it can also be a "break-in" type of issue, but the discoloration is definately due to heat. If you break in your bike according to the manufacturers recommendations, I believe the pipe will be less likely to discolor, because it isn't subjected to high temps until it effectively gets "heat treated" over time. Once the engine's broken in, if you replace the pipe (and you ride hard), you will definately see discoloroation (happened to me when I replaced my exhaust last year - discoloration on the new mid-pipe, but there was hardly any on the original one). If you break in your bike on the dyno (and ride it hard), I think the odds are better that you'll see discoloration.

[Akira7R]

Yes , just the header part about 5 inches , I have a new full Muzzy , but also my bike doesn't run smooth , arround 5000-6000 rpm it's breaking up badly. I was told that i should replace my fuel filter first then the spark plugs and if still not good then i need carburator adjustment.

[Anonymous]

If you replaced the entire exhaust system (with something different), you need to get it rejetted (or so I've been told). This will smooth out the power delivery.

[scott_tiller]

If you need any help let me know. I have a '95 zx7 which is the same as the '94. I've spent a fair amount of time getting mine jetted and tuned to run well after making a few mods to it.

Trina

[vtr1000rider]

Typically when replacing the exhaust system on a carberated bike you'll want to re-et in order to smooth out the power bands. Typically air intake work might need to be done as well, depends on the back pressure etc.

I need the same help. I have replaced my stock exhaust on my VRT1000 with staintune exhaust. It sounds great, but I think I've lost some of my power range. Anyone have exprience in re-jetting a big V-twin???

Or any shops in the denver metro area you'd recommend for this?

[Akira7R]

Well i buyed the bike last year in november like that with the new Muzzy , it was okay because it was cold out there in Golden , the bike was runing good enough. Now because of the worm weather things are changeing , anyway i'm going to change fuel filter , spark plugs , see what's hapening , then i might ask for help .
Thanx.

[Hoopty]

Or any shops in the denver metro area you'd recommend for this?

Give TK Motorsports or TFOG a call, either one will take care of you. :)

PS- TK has a dyno! :D

[Anonymous]

Typically when replacing the exhaust system on a carberated bike you'll want to re-et in order to smooth out the power bands. Typically air intake work might need to be done as well, depends on the back pressure etc.

I need the same help. I have replaced my stock exhaust on my VRT1000 with staintune exhaust. It sounds great, but I think I've lost some of my power range. Anyone have exprience in re-jetting a big V-twin???

Or any shops in the denver metro area you'd recommend for this?

When Bart was at Performance back in the day, he did the jetting work on my superchicken after I put on my Devils and a K&N filter. I got nearly 10HP increase at the wheel, and other superchicken owners are routinely surprised at how much I got out of it with what are essentially bolt on upgrades. TAKE IT TO BART. Let no one else jet your bike, period.

Oh, go spend the $45 and get a 4 degree Factory ignition advancer. You'll need a new right-side cover gasket to put it on, and it will take you about an hour including scraping the old one off (be careful and get a tube of grey permatex, since you'll nick the soft aluminum most likely). The result will be much improved throttle response, and maybe an extra HP or so. I can help you put this on if you don't feel comfortable doing it, happy to help another Chicken owner. :) (And the 4-deg advancer is pretty much the universally-agreed best one to get, the other ones either advance it too little or too much.)

One more thing, if you're not running 85-octane fuel, go ahead and try it. The chicken's compression is low enough that you can at this altitude, the mid and high octane pump gas slows the combustion too much and you lose power. I've been running 85-O for a few thousand miles now and it's working great! ;)

[scott_tiller]

Akira7r, I don't know much about other bikes, but I know my bike and I can tell you from experience that my bike runs like crap in cold weather, but runs great in warm weather without changing a single thing on it. I don't know if its a zx7 thing or a carb thing.

I would go ahead and check your fuel filter and change your spark plugs, but I would wait until the weather gets nicer and then see how it runs before messing with the jets.

Trina

[Akira7R]

Yes , sunday i hope i'll have a new fuel filter and spark plugs NGK , also i'll change Silkolene . I wont touch the jets for now , but i would like a jet kit maybe next month .My problem is with high speed rideing , in forth , fifth gear i loose power.
Hey scott-tiller , i work at Conoco near Pepsi Center , u can see my ride if you ever pass by , i work mostly afternoons , i would like to talk with you man .

[KooLaid]

RALPH, you ran the 85 on your FI gsxr??? Or which bike? I kept getting the idea that I would have to run higher octane w/ the 4 degree on my F4i.

[Akira7R]

Finaly i adjusted my carbs , it was runing lean , i have a jet kit and it was badly jetted , i changed the oil and spark plugs. It runs much-much better now , i can actualy use my fifth and sixt gear to , hehehehe.
I need a K&N air filter and a fuel filter and my bike should run good , i also buyed a set of 171 tools today ;) .
I'm all happy now , but i still have a licking at my clutch to fix .

[Anonymous]

RALPH, you ran the 85 on your FI gsxr??? Or which bike? I kept getting the idea that I would have to run higher octane w/ the 4 degree on my F4i.

No no no... 85 in the superhawk. It has 9:1 compression, which is low by sportbike standards (GSXR is ~12:1 IIRC). I would never run 85 in a GSXR, even at this altitude, though any octane the race fuel comes in is fine.

Remember - Octane is designed to retard, or slow combustion! It is designed for high compression situations (i.e. forced intake, or with headwork/custom pistons etc) to prevent pre-detonation of the fuel by compressing it too much. Now, remember the part about forced intake, the same goes for altitude - at lower air pressure (higher altitude) you will have less air to mix with fuel in the cylinder. If more air = higher octane to prevent detonation, then less air means you can get away with lower octane, to a point. And low air + low compression = low octane is allowable.

On the uberchicken, there was (at least to me) a noticable difference between premium and regular pump gas, with the cheaper gas being better. There isn't a difference in quality between them, just octane rating, so the trick is to find the lowest octane your bike will sustain without knocking/pinging (which is a sign of detonation, which will do very bad things to your motor if left long enough), since that's the point where the most power will be developed.

I *think* on the F4i you should be able to get away with at least mid-grade up here in Colorado (remember to increase the octane if you find yourself at sea level), depending on the bike's compression. You can always try the low grade, and if it starts knocking, mix it with premium to average the two out and get it back up.

Also - ignition advance has nothing to do with Octane AFAIK. The advance is just the point where the plug fires, ideally you'd want the lowest octane (quickest burn) possible w/o knocking, with the spark just before TDC, hence the point of the advancer.

[yakuza]

The F4i manual calls for 87 octane if I remember correctly (stoopid bastards at Loveland Honda stole my owners manual a couple years ago) and I ran the latter half of the race season on 85 octane with no issues. Your mileage may vary...

[Anonymous]

You can typically use at least a grade lower than what the manual calls for, at this elevation. Those are written for sea level, so adjust accordingly. ;)

[scott_tiller]

Glad you got your bike running better.


I need a K&N air filter and a fuel filter and my bike should run good , i also buyed a set of 171 tools today ;) .

When I took my bike in last winter to have the valves done, Marv (mechanic @ Rocky Mountain Kawaski and mechanic for Ricky Orlando who used to race a zx7 back in the day) told me that the K&N is actually more restrictive than the stock filter. He told me to throw my stock air filter back in. He said for most bikes the K&N is an improvement over the stock, but on the zx7 it is not. But I'm sure everybody has an opinion on this.