I thought you might be interested in my experiences with my 1992
ZX1100 C3. I have made over 20 dyno runs with this bike trying different
things.
My results follow:
6000 miles - Bike bone stock
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120 rear wheel HP @ 9500
Rpm. The curve was very smooth.
I then added a K&N filter, Dynojet Stage I kit
(using DJ 136 main), a Factory ignition advance, and a 16 tooth front
sprocket.
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125
rear wheel HP @ 9500 Rpm. The curve was still very smooth. I also gained a
little midrange HP and the powerband looked slightly wider. The gearing
change shifted the whole curve slightly to the left. What that means is that
more HP is available to the rear wheel at the same road speeds, or the same HP
is available 5 MPH sooner, compared to the stock gearing. I lost about 5 MPH
in speed at redline from the gearing change. All of this is due to the fact
that the motor now spins slightly faster due to the gearing change. The
gearing change WAS NOT responsible for the change in peak HP.
I still wanted more power so I figured that an aftermarket 4-1
pipe was the way to go. I looked at all pipes on the market and then went
with the V&H SS2R. I went with this pipe for a few reasons. Number one
was noise level. This seems to be the quietest 'performance' pipe on the
market. I also liked the nickel plated finish and I feel this is the best
looking pipe available. I was also considering the Muzzy pipe and was told
by various tuners that it might be worth a few more ponies over the SS2R but
I was willing to sacrifice 2 or 3 HP for a quieter system. I assumed that
the new pipe was going to make the motor run lean up top so I opted to use
the DJ140 main rather than the DJ136. My results follow.
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136 rear wheel HP @ 10500 RPM. The curve now had a double dip between 5500
- 7500 Rpm.
Click here to check out a MPEG movie of my ZX11 on the dyno.
(Dyno.mpg - 673 KB)
The SS2R added a lot of high rpm horsepower. Not only did
I gain 10 peak HP over the stock pipe, the SS2R carries its power peak right
up into the rev limiter. The powerband looks much wider on the dyno sheet.
The bike no longer runs out of steam after 10000 Rpm, it SLAMS right into
the rev limiter (this can be a little dangerous when riding a wheelie at 65
mph). The motor now carries over 128 Hp from about 8500 Rpm to redline. At
some points in the dyno chart the SS2R produces over 15 more high Rpm HP
then the stock pipe. A race pipe, like the Muzzy, with an open baffle would
probably produce more peak HP. Remember that these dyno runs are not using
the benefits of the Ram Air system.
I tried almost everything to eliminate the double dip between
5500-7500. I tried going leaner and richer on both the main jet and the
needle jet but I was not able to eliminate the problem. But I was able to
establish that the DJ140 was the main jet that the motor liked best (and
this was without the benefit of Ram Air). I have the needle currently set
on groove 4. Please note the needle jet has absolutely ZERO affect on a
dyno run. It seems that the carbs get on the mains very quickly and the
needle has basically no affect on a dyno run. The needle will affect part
throttle cruising jetting which is not seen on the dyno. The double dip
caused by the SS2R never drops more than 2 HP below the stock pipes smooth
curve and by 8000 Rpm there is no contest between pipes. I spoke to Dynojet
tech services and they told me that I would never be able to eliminate this
double dip in the dyno curve. The technicians said that the ZX11 has a lot
of cam overlap and needs backpressure to make good HP at low RPM. They said
to eliminate the double dip I would have to reinstall the stock pipe. I was
curious to see if they were right so I reinstalled the stock system and
DJ136's and found out they were right. A couple of tuners said that I could
eliminate the double dip caused by the SS2R by playing with the cam timing.
I choose not to try this because I was afraid of what would happen to my
part throttle driveability which is fine as is. I also tried to vary the
valve clearance to see how it would affect the dyno curve. This did have a
very small effect on the double dip but not enough to eliminate it. It did
not seem to have much affect on peak HP or the powerband width. In the end,
I left my clearance within specs, but towards the looser side, and
reinstalled the SS2R and DJ140's.
I spoke with Vance and Hines tech support and found them to be of
absolutely no use. I faxed them my dyno printouts and they promised me that
they would work with me to eliminate my double dip. The promise was never
fulfilled. I would not recommend dealing with these people unless you like
to be told lies and don't mind people promising you return calls which never
come.
On the street the SS2R and DJ140 does not feel any stronger than the
stock pipe and DJ136 below about 7500 RPM. When I reinstalled the stock pipe
and DJ136's(as per Dynojet's suggestion) and road tested it I think that the
Stock Pipe and DJ136 DID feel a little bit stronger down low than the SS2R
and DJ140. I don't remember how the stock pipe and stock Keihin jetting felt
so I can't compare the SS2R to that down low. But after 7500 it is
absolutely no contest. The SS2R explodes with the front wheel flying high
every time. First gear power wheelies come totally unexpected. No
clutching or throttle whacking is required. You can just sit back and hold
the throttle open and when it hits about 8000 the front wheel comes way off
the ground on its own and doesn't fall until you smack into the rev limiter.
I also feel that even with the shorter gearing the bike is capable of a
slightly higher top speed than it was when stock. When the mags tested the
top speed of the ZX11 it reached 175 MPH at about 10,700 RPM. I don't think
my bike would have a problem pulling redline in top gear.
When riding at normal speeds the SS2R is a very quiet pipe. On the
highway you can't even hear it. This pipe stays quiet until you hit the
powerband at full throttle. Then its considerably louder than stock but
still quieter than the race pipes I have heard.
I recently raced a stock 1995 ZX1100 D and it wasn't even close. We
first raced from a first gear 10 MPH roll. The '95 D model took off first,
then I whacked the throttle wide open (no clutching and at low RPM). I took
off with the front wheel about 60 degrees off the ground and blew by him and
kept pulling away. I actually thought that he would beat me right off the
line with his stock pipe and jetting. I guess my gearing change and the
fact that he was running the stock Keihin jetting and air cleaner hurt him.
We also did a few high speed passes which always ending with me easily
pulling away. During these high speed runs I reached speeds of about 173 MPH
as indicated on the speedometer.
As to whether these modifications are worth it is up to
you. I would definitely recommend at least the Stage I jet kit, K&N air
filter and the ignition advancer. This will keep your bike as quiet as
stock while adding at least 5 peak Hp and widening the powerband. The
gearing change will also add a little pep while only taking away about 5
seldom used MPH in top speed. If you are the type of rider who seldom sees
redline and just cruises around town this would be the perfect setup. If
you are like me and trips to the redline are a daily occurrence then I would
recommend a 4-1 pipe. You may lose a little (very little) down low but the
rewards in the upper RPM are worth it.
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