Short manifolds

[koko64]

I have been toying with the idea of testing short manifolds on my '95 900 Monster. Doing so apparently moves the torque peak higher up the rev range increasing horsepower. Everything has it's cost however, and it appears that short manifolds take torque from the bottom end altering the character of the engine.
The Hordepower and MPS websites show interesting dyno charts regarding this modification.

My bike so far has JE hi comp pistons, dialled cams (Vee Two pulleys), porting, open air box and jetted stock CV carbs (oh and Termi slip ons). I am about to fit Dyna coils.
I have a spare set of stock carbs to play with. I have thought of using a stock CV carb from each set, running K&N pod filters, and reducing the length of the stock manifolds a couple of inches. A couple of inches is all I can take off without having to move the large frame cross member under the battery box. I think I can clear the small cross member near the front carb if I angle things right. If I do this I will make it reversable by putting the carbs back together on another set of manifolds.

I have read reports on Doug Lofgren's site (MPS) which indicated the need for frame cross member modifications in order to fit FCR's on Malossi manifolds. Anyone tried stuff like cut down stock manifolds, separating the CV stock carbs or trying other types of carbs and manifolds that might fit without having to cut and relocate the frame cross member?

Cheers 
Tony.

[MotoCreations]

To be honest, I'd sell both sets of CV carbs and just order the standard FCR's (or find a used set).

a) even 41FCR's on the long manifolds will outperform what you are intending.  (and be an hour swap at most)
b) go polish and cleanup the long manifolds as it helps some
c) if you get separate FCR's and short manifolds -- it's the best setup even with the carb synch'ing headache.

The CV stock carbs -- not worth the headache in my personal opinion.  I know Doug Lofgren did his magic guru tuning skills on some and got them to work quite well.  But never better than FCR's.

Talk with Chris @CA-Cycleworks in regard to the early Monster frame crossmember with shorties and individual FCR's.  I don't remember having to modify a frame years ago when I put split 39FCR's on a 99 M900.  41FCR's are the same size physically.  I just fabricated a set of new aluminum intake manifolds -vs- using the Malossi's as they weren't available. (I borrowed a set to jig against)

Definitely check the availability of the short Malossi intake manifolds.

If you like tinkering in the garage and are mechanically adept, definitely do the individual CV configuration and report back online as to the setup and then tuning to make work.  There would be a few people interested!

[koko64]

Thanks heaps Mark

I once had a Superlight with the same mods as my M900, but with 39FCR's. A set now would complete the package. You are right; long or short manifolds, FCR's are vastly superior instruments to the stock CV's.

I previously cleaned up the stock manifolds. Left a machined finish and opened the radii. Ensured the end of the manifold ran nicely into the port. I consulted a friend who tunes race cars (he supervised me)!
I was amazed how rough and unfinished they were from the factory. Rough cast sections, casting burrs, lumps and casting ridges.
I can report that carby icing is noticeably reduced since I did it. Not sure if it's a coincidence. Fitted the jet kit previously, so that wouldn't be why.

You've got me thinking.. K&N barrel filters $110-00, 2 into 1 throttle cables $60-00, dyno runs x2 $200-00 (it's never right the first time), Malossi manifolds?, machining stock manifolds?, fabricating ignition gear bracket (for me, a whole morning), flexible race fuel lines $30-00  and fittings (carby to carby). I'll also have to buy spare manifolds and keep a throttle shaft if I regret it.
Vs
$1000-00 Aus for 41 FCRs shipped to Australia (they are $1900-00 Aus to buy here). I also have good jetting settings for them from the previous bike with the same modifications. Say I get $200-$400-00 for two pair of CV carbs.

I love DIY, cheap, in your own garage, bang for buck horsepower. You know, 6 horsepower for $200-00 rather than 10 horsepower for a Grand.
I can do it all in a day and night if the manifolds are ready to go. It will only be cost effective if my machinist friends will help me for a six pack of Bourbon and I get the filters cheap. Good advice Mark. I'll consult further.

Time to email Doug, Brad and Chris.

Cheers and thanks again
Tony.

[koko64]

G'day Mark

Short Manifolds Dead in the Water

Both Chris and Brad have indicated that short manifolds on my Monster require frame mods I am unwilling to do. To get the correct manifold length to be worthwhile is not possible without relocating a frame cross member which is right where one carb needs to go. I can shorten them, but not enough.

Chris gave quite a definitive answer and I found some previous correspondence from Brad in one of my files supporting  his view. I have not contacted Doug yet but will enquire if he still does his taper boring, etc of CV carbs and how much this costs. There is no one I know of down here that does this work anymore and if it isn't cost effective to taper bore the stock carbs then I will be on the market for some FCR's.

After much testing and discussion with Brad my stock carbs are at a good compromise setting; for what they are..
I will have to see what I can do with FCR's Vs Taper Bored CV's. As I indicated to Chris; time to start saving..

Thanks again
Cheers
Tony

 

[greenmonster]

As everyone else will say, you will not regret FCR`s.
I would add an programmable ignition like Ignitech TCI-P4 when you have hicomps.
Next time on dyno you`ll be able to tune fuel & ignition and get the most out of your mods.

[koko64]

Thanks
I miss the FCR's from my Superlight. It wheelied without trying.
I retarded the ignition 3deg at the pick ups. Good thing Brad explained it to me and my wife teaches Maths!
I need a petition from DMFer's to support the FCR purchase (to present to my wife ). Those carbs are a necessity!

[junior varsity]

Chris at CA-Cycleworks wants you to just buy a binned Monster's engine from a newer 1000 or 1100 if you want horsepower. And he's right. Not that sprucing up the ol' M900 isn't fun (i like to tinker with mine all the time).

I've been putting the FCR's off for awhile, stupidly. Here's a list of some other things I've done with the bike that you might consider:

VeeTwo Adjustable Cam Pulleys
Nichols Lightweight Flywheel
FBF Open Airbox Ring/BMC Filter
DynoJet Jet Kit (blech. its 'ok', but no FCRs)
Sil Moto Spaghetti Headers
NCR/Sil Titanium Low Mount Round Pipes (or any other well-flowing pipe setup)
CA-Cycleworks' DynaCoils Kit
Ignitech Sparker TCIP4 Programmable Ignition
ER Racing Quickturn Throttle and Cables (almost, too quick)
Nichols Crankcase Breather
GSG Moto Oil Fill Temp Gauge
Upgraded Starter Wires, Ground Wire

[koko64]

I have quite a few simlar mods to my motor.

JE pistons, open air-box, jet kit, dialled cams (Vee Two Pulleys), porting, light flywheel (-1kg machined off) and clutch (Vee Two, Barnett), Termi slip-ons, ignition retarded 3 deg at the pick-ups and Dyna coils are ordered.
Just need one more thing to complete the package..

I like the look and ergonomic "fit" of earlier Monsters.
Here's to older Monsters..
Cheers
Tony