BruceSki
Formerly Motoman25
- Location
- Long Island
all of the aftermarket manifolds are without a crossover
Filling Crossover
- Thread starter surferdude345
- Start date
waxhead
wannabe backflipper
- Location
- gold coast
mate crossover is a bad thing and will send your sister to the whore house and your mum to the Brothel.
your sister will end up the mother of your two headed children
yes people its thats bad
your sister will end up the mother of your two headed children
yes people its thats bad
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Dustin Mustangs
uʍop ǝpıs dn
- Location
- Holland, MI
From what I have been told the correct answer to this depends on what carbs you are running. And that for stockers it is normally not worth the effort.
- Location
- Near Seattle WA
The AB Epoxy is lower priced (and lighter) than Devcon. It has no metallic content, so if you have any problems it simply gets crushed by the piston and spit out the exhaust port. $34.95
http://www.watcon.com/Catalog_Pages/AB_Putty.htm
Thanks,
Randy
http://www.watcon.com/Catalog_Pages/AB_Putty.htm
Thanks,
Randy
- Location
- South Africa
If you read what GroupK, etc say about filling crossover, they are only worried about deteriorating WOT signal. A crossover on a twin cylinder is in place of a boostbottle on a single cylinder. It cleans up low speed carburetion, delivering more power on the low-end, same reason some like to run a single carb on a twin.
That begs the question if he rejetted/tuned the carbs when he switched back and forth.
SXIPro
JM781 Big Bore
- Location
- Here on the 'X' mostly
Exactly right. You absolutely must rejet if you fill the crossover, at least on stock 38s. If not you will have a low speed stumble or hesitation. Ask me how I know.
To me it wasn't worth it. I yanked the filled one and threw my stocker back on. So if anyone wants to buy a stock manifold with the crossover nicely filled...send me a PM.
chriselmore_1
high on resin
- Location
- san jose ca
how much?
BruceSki
Formerly Motoman25
- Location
- Long Island
I've got one for 30 shipped. check page one of this thread.
- Location
- South Africa
I did some testing on this yesterday. I made custom crossover on my SXR 800 engine with 48mm annular discharge carbs, made a big difference on acceleration, (and yes my carbs were jetted correctly before I did this)
Got the slight whiplash today to prove it
Got the slight whiplash today to prove it
Freakrider
X247
- Location
- Tampa Bay area
So are you saying your ski had better bottom end by adding a crossover ?
- Location
- South Africa
Yes, much better
If you read the research done by companies/engineers, they all say it gives cleaner/better response which is what we are after. A GroupK article refers to the downside of deteriorating signal at prolonged WOT, something that won't affect a freestyle machine. All the AM manifolds were originally made for racing
Eric Malone keeps the cross-over setup on the backflipping Q8 with SXR motor, I think he knows more than most of us
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Schmidty721
someone turf my rails
- Location
- WI
When you say you added a "cross-over" what exactly did you add? Is it an external piece, ie one boost bottle connected to both intake ports?
- Location
- Idaho
I just got a spare set of carbs and manifold that was modded by Art at Jetworks. The cross over in the manifold is filled. I have yet to install and test.
Freakrider
X247
- Location
- Tampa Bay area
again this is what John at Jetskisolutions believes strongly...He states that we all are making a big mistake by filling in the crossover...we are losing bottom end hit.
- Location
- South Africa
I have a pipe joining the 2 adapter plates I was using for the boostbottles, no boostbottle at the moment just a pipe and 2 elbows joining the pipes the that used to connect to the 2 boostbottles. See this thread: http://www.x-h2o.com/threads/12132-Boost-Bottle-for-freestyle/page7&highlight=boost+bottle
- Location
- Near Seattle WA
Connecting the two cylinders will make the power delivery smoother, and you lose the capabilities to individually tune each cylinder. This works best on a "single carb application" This is what I found with testing, so its based on my opinion only.
Regards,
Randy
Regards,
Randy
- Location
- South Africa
I have played with individual carb settings a lot, eventually landed up with the best setting I could get. Perfect acceleration was there but at constant low throttle position it was rich which is needed for rapid throttle opening as no accelerator pump. Adding the crossover cleared the rich constant low speed and I only had to open the high speed screws a bit. If you read the Y.E.I.S. technical paper, they speak about the torque dip just before the motor comes on the pipe due to pulses from exhaust affecting scavenging. They also state that there is less effect with a PV motor. A crossover relieves the pulse to the other cylinder while the boostbottle stores that pulse and returns it back to that cylinder.
Just my findings from researching and testing on my ski
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