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Author Topic: Intake boots  (Read 1330 times)

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Offline Blue400

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Intake boots
« on: August 20, 2010, 03:36:46 PM »
I had ordered up some banshee intakes with the crossover tube off ebay, i had to trim the stuffers off them to get them to fit, i ordered them because my existing intakes were starting to crack, when i took the intakes off the bike, and held one of them next to the banshee intakes i just bought, i noticed the inlets on the ones i had were smaller than the banshee inlets, i didnt think much of it, well i got them all mounted up and started the bike, the first thing i had to do was turn the idle down cause it was at like 3500, and i noticed the bike had a deeper sound to it, and a much healthier "cackle", so i threw my bucket on my head and went out for a ride, when the motor was not heatsoaked, i almost flipped it over backwards in 1st just by wacking the throttle from low RPM, i about shit myself, thats another issue with my bike that got figured out by mistake. Im wondering if maybe years ago i didnt replace those intakes, but i dont remember, if i did, could it be that those intakes that were on there were off a 250 or a 350?

Offline SoCal250

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Re: Intake boots
« Reply #1 on: August 20, 2010, 03:56:37 PM »
As you discovered, the idle needs to be adjusted down when the cross-over is added. That is completely normal.  :thumbsup:

Your old intakes are probably just stock RD400 units, as they are smaller than the Banshee pieces because the reeds on the two bikes are very different in size. This may shed some light on the topic.  Reed_Intake_Comparison
« Last Edit: August 20, 2010, 03:57:48 PM by SoCal250 »
91 TZR250R (3XV);  89 FZR400W
79 RD400F Daytona;  77 RD400D - mod project
75 RD250B (350 project);  75 Yamaha RD200B (in boxes)
75 RD125B (stock,<1K mi);  75 RD125B (project: RD/TA200);   05 FZ6
For Sale: 02 Aprilia RS250 Cup
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Offline GSXRDman

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Re: Intake boots
« Reply #2 on: August 20, 2010, 03:57:43 PM »
I've tried the OEM, Banshee, UPP & Chinoy.

My favorite by far (now) is the banshee....has the locating pip for the stock carbs, more positive clamping with the banshee clamp that goes w/i, MORE solid than the OEM...oem is weak, doesn't leak like the chinoy,  is more better fit than UPP, has the rubber sealing ring on the backside.  I've reused a banshee set w/ an application of yamabond 5? (the black rubber sealant, not the case sealant).

Just a good intake manifold and (now) WAY cheaper than the inferior OEM.  Plus the Spec II pipes really love the crossover...that's probably what helped you flip in first.  that volume helps way down low right off the throttle.  Nice to be able to pull off from a stop easily like that.
RD400F modded to RD400 specs, 29.3mm R5 carbs, 240 mains, 2mm shroud 169-P2 needle jet, 5DP7-5 (full rich), stock R5 slides (2.0), #30 pilot @ 7/8ths airscrews.  2010 Spec II "classics", Y-boot UNI, TDR yellow one piece reeds, B9ES plugs / stock gap, 1.9mm BTDC.  Amsoil Interceptor 24:1, pingel tap!

Offline Blue400

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Re: Intake boots
« Reply #3 on: August 20, 2010, 04:04:26 PM »
Thats very interesting socal, seriously though down around the 2000-4000 range it sounds like a different bike, much nicer. My reed cages are aluminum, which 400s had plastic ones? They are a bit larger i see, and why?

Offline SoCal250

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Re: Intake boots
« Reply #4 on: August 20, 2010, 04:13:44 PM »
Thats very interesting socal, seriously though down around the 2000-4000 range it sounds like a different bike, much nicer. My reed cages are aluminum, which 400s had plastic ones? They are a bit larger i see, and why?

I believe the plastic ones were a Euro-only part. That image file is from a German website.
91 TZR250R (3XV);  89 FZR400W
79 RD400F Daytona;  77 RD400D - mod project
75 RD250B (350 project);  75 Yamaha RD200B (in boxes)
75 RD125B (stock,<1K mi);  75 RD125B (project: RD/TA200);   05 FZ6
For Sale: 02 Aprilia RS250 Cup
Sold:  85 RZ500N V4



Offline Blue400

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Re: Intake boots
« Reply #5 on: August 20, 2010, 04:14:37 PM »
Kevin i actually have FPP pipes on mine.

Isnt there a way to lessen the heat soak by tightening up the squish in the heads a bit? Does it work?

Offline Dave Freist

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Re: Intake boots
« Reply #6 on: August 20, 2010, 04:20:32 PM »
250s and 350s have the same intake manifolds. Heh, heh...I was the first one AFIK to use 'em and yep I had the same high idle when I first started it up. This was back in '99. The crossover will help banish the typical mid-range rich spot caused by out-of-phase exhaust pulses returning up the pipe and through the engine. Works great, eh?  I'd never have an RD wilthout 'em...
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Offline Blue400

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Re: Intake boots
« Reply #7 on: August 20, 2010, 04:34:02 PM »
Heck yes Dave, if i would have known the gain was that much, i would have put them on it a long time ago,  i was giggling like a little kid when i let off, it almost scared me, i just hope i didnt blow the fork seals out coming down.  :lol:

Offline Dave Freist

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Re: Intake boots
« Reply #8 on: August 20, 2010, 04:53:53 PM »
Blue, ya oughtta see what happens with those manifolds/crossover tube, SCR Stg. II.5 porting, head work and big TM32 carbs plus SpecII chambers :bowdown:. I hadda go up a tooth on the countershaft sprocket; first gear became useless and its still one scary little orange laser. :rock:
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Offline Blue400

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Re: Intake boots
« Reply #9 on: August 20, 2010, 05:48:53 PM »
Awesome, im geared down a tooth from stock on the counter shaft right now. Maybe someday i will get into that, but now that the thing is finally running good, im gonna enjoy it.  :cheers:  Although i still wonder about the cutting of the heads if it prevents as much heatsoak, you know anything about that if it works or not?

Offline GSXRDman

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Re: Intake boots
« Reply #10 on: August 20, 2010, 06:01:05 PM »
heatsoak.  Are you saying you are smelling some  egninge overheating?  Sounds like you  may have some jetting to do.  

you have a 400 right?  I jetted up on my pilots until i got rid of the heat smell.  Easy way to tell if the pilot is too small is to cruise say, 35 to 50 and let go of the throttle...let it wind down on zero throttle.  If you have surging off throttle, it's too lean.  Either play with the airscrews (turn them in an 1/8th at a time until you reach 1/2..if good at 1/2, go larger on the pilot and keep going larger until you can get it nice near 1-1/4 to 1-1/2 turns on the airscrews.

It should easily pull you up a hill in 2nd gear w/ the throttle held at 25 mph too.

I think after RB Designs ported my 400, that i could use the crossover tube on the intakes.  Before the port, it didn't like them (FPP) pipes.
« Last Edit: August 20, 2010, 06:04:56 PM by GSXRDman »
RD400F modded to RD400 specs, 29.3mm R5 carbs, 240 mains, 2mm shroud 169-P2 needle jet, 5DP7-5 (full rich), stock R5 slides (2.0), #30 pilot @ 7/8ths airscrews.  2010 Spec II "classics", Y-boot UNI, TDR yellow one piece reeds, B9ES plugs / stock gap, 1.9mm BTDC.  Amsoil Interceptor 24:1, pingel tap!

Offline Dave Freist

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Re: Intake boots
« Reply #11 on: August 20, 2010, 06:25:42 PM »
Sqush is VERY important. Its running .040 squish and l45 lbs. compression and runs nice and cool plus more bottom-end power. On 87 octane gas. Cheapass Valvolline 2-stroke oil and the thing runs HARD w/no detonation. I've had several RD-350s and NONE of 'em ran like the orange laser. Last year I let an old motocross racing buddy ride it; brought it back in 5 mins. and handed me the key. "That thing is gonna take me awhile to get used to it. Scared the crap outta me in 2nd."
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Offline mkane63t

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Re: Intake boots
« Reply #12 on: August 20, 2010, 06:59:24 PM »
 Who cares about 1st & 2nd. What about 3rd thru 6th?
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Offline Dave Freist

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Re: Intake boots
« Reply #13 on: August 20, 2010, 07:06:40 PM »
Big-time rush, goes like hell. 6th gear at 60 and wanna go? No problemo. Just crank on the throttle and fly... With the stock sprocket I kept looking for another gear that wasn't there, I was already topped out on gears... :thumbsup: I got exactly what I wanted from Scott Clough. The guy is a genius. :bowdown:
« Last Edit: August 20, 2010, 07:10:54 PM by Dave Freist »
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Offline Blue400

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Re: Intake boots
« Reply #14 on: August 21, 2010, 07:32:00 AM »
Kevin what i mean by heatsoak is after i ride it for a while, it loses a little power, the pilots are fine, if im sitting in neutral and rev it up, it idles down better with this intake setup than it did before. And it pulls just fine at 25 mph. Im gonna have to do a solder/squish test one of these days, to see what it has.