I'm considering fabbing an alternate battery box and installing pod filters on my old friend '01 M750.
Pertinent mods to date:
=39FCRs installed in '03 with jetting, etc still as supplied by CA Cycleworks / Chris Kelley
=open-top airbox (no top, old skool Al frame to hold the K&N flat filter in place)
=Staintune cans w/out the silencer plug
=Blue Dyna Coils from CA Cycleworks, vintage '03
=Nichols flywheel
Questions:
? What is the K&N part number for the pod filters to fit 39FCRs ?
? Will this setup run leaner than the current open-top airbox ?
? if yes, what are specific recommendations for jets/needles/screws for a safe (slightly rich if anything) point-of-beginning for this setup ?
This project would be done strictly for aesthetics to open-up the frame side view. Should I expect performance compromises? The M750, underpowered though it may be, is perfectly suited for my use for legal speed twisty-road therapy in contrast to my (also loved, and highly modified) '04 Concours camper bike.
Thanks in advance!
I dyno tested pods against open airbox on a 900. I'll check my data and get back to you. The pods that fit are K&N RU 1750. IIRC. California Cycleworks list them.
Power was similar (on a dyno), weight savings significant, better air cooling flow to rear cylinder, but bloody loud.
Other members have done this on a 750 and should chime in for sure.
Thanks, koko64
Do you recall if you had to change the carb jets/needles when you made the conversion on your 900 (I assume FCR 41s)?
Yes, sorry, FCR41s.
I dont think you will find much more than a size or two difference on the main jets and one notch on the needle. I found from ega readings that the pods dont quite flow as well as a properly prepared open airbox, but the margin in streetable performance is not great. You may find that the jetting for your open airbox is a good baseline for the pods. The 750s appear to hold their power better to redline than the 900s.
Getting the bike to carburate cleanly off a closed throttle may require you to try different slow air screw and IMS settings.
If you want to keep the airbox you can pm me for some custom mods. I dont think pods are worth it unless for cleaner looks.
Quote from: koko64 on July 17, 2012, 11:01:00 AMI dyno tested pods against open airbox on a 900. I'll check my data and get back to you. The pods that fit are K&N RU 1750. IIRC. California Cycleworks list them.
I don't think I did a before and after on the airbox to foam filters (I used UNI filters, not K&N pods) as I did them the same time I installed my FCR's. IIRC, The combination was good for about 5hp on top and 8ft/lbs of torque around 3800 rpm.
QuotePower was similar (on a dyno), weight savings significant, better air cooling flow to rear cylinder, but bloody loud.
Music to my ears when I whack the throttle open. [thumbsup]
Quote from: koko64 on July 17, 2012, 04:16:05 PM
.... If you want to keep the airbox you can pm me for some custom mods. I dont think pods are worth it unless for cleaner looks.
Opening up the frame below the tank for 'cleaner looks' is the sole reason to consider the project. If I can just maintain the current performance while accomplishing that, I'll be happy.
Your current jetting should be a good start.
I can only speak for my 900, but the pods made it a little leaner low in the rev range on small throttle openings and a little richer in the top half of the rev range and throttle position.
Put them on and see if the idle falters and how tractible it is rolling through the throttle range. Try and feel for any variation in performance, particularly any pauses in the power delivery.
Check out Patrick Burns FCR tuning guide. CCW has a link.
My 2001 M750 is F.I. and i have a hoodie shirt cut and strapped over the short horns I have a short single can [pipe] on one side , do get a few pops every now and then but very very mild and not to often .
Quote from: H-2 CHARLIE on July 18, 2012, 12:32:25 AM
My 2001 M750 is F.I. and i have a hoodie shirt cut and strapped over the short horns I have a short single can [pipe] on one side , do get a few pops every now and then but very very mild and not to often .
Dyno Test!
Open airbox Vs Pods Vs Hoodie.
[laugh]