So any progress???
Anyone running a single Full Spectrum?
- Thread starter Matt_E
- Start date
So any progress???
Yes!!!!
I had her sitting at 2.0 N&S, 95g spring, 130P and 150M. It ripped!
A bit rich (?) off the bottom, and a hesitation right off idle.
I did more tuning, but long story short, I have an electrical issue - probably the coil.
I will fix that, and get back to tuning.
I am confident it is very ridable with the above config, just not ideal yet.
And let me tell you, HOLY CRAP!!!!
Last year, I ran this engine with slightly different cylinder porting, no case porting, dual 44's with VForce 2 reeds, and MSD Digital Total Loss.
Today I ran that same engine with updated cyl porting (I paid more attention to detail, matching everything, and porting for lowend), nice case porting, absolutely stock electrics, single carb intake with Boyesen cages and 2-stage reeds, and that single 48 Full Spectrum.
I can honestly say that it hit just as hard from mid-range on as previous year's config. :biggthumpup:
I am excited to get the electrical issue worked out and the carb tuned JUST right. It will unreal. :biggthumpup:
I had her sitting at 2.0 N&S, 95g spring, 130P and 150M. It ripped!
A bit rich (?) off the bottom, and a hesitation right off idle.
I did more tuning, but long story short, I have an electrical issue - probably the coil.
I will fix that, and get back to tuning.
I am confident it is very ridable with the above config, just not ideal yet.
And let me tell you, HOLY CRAP!!!!
Last year, I ran this engine with slightly different cylinder porting, no case porting, dual 44's with VForce 2 reeds, and MSD Digital Total Loss.
Today I ran that same engine with updated cyl porting (I paid more attention to detail, matching everything, and porting for lowend), nice case porting, absolutely stock electrics, single carb intake with Boyesen cages and 2-stage reeds, and that single 48 Full Spectrum.
I can honestly say that it hit just as hard from mid-range on as previous year's config. :biggthumpup:
I am excited to get the electrical issue worked out and the carb tuned JUST right. It will unreal. :biggthumpup:
RiverRat
.......
- Location
- Louisville, Ky
I am all about the big carbs :biggthumpup: Single or dual.........preferably duals :biggrin:
D-Roc
I forgot!
- Location
- Dirty River Rider
Big Carbs Rock!!! Sounds like your very closely jetted to what i ran last year in my single 48.
D-Roc
I forgot!
- Location
- Dirty River Rider
Now that i looked it up its wasn't as close as i thought. 2.5 N&S, 115 gram (20-22 lbs) 135 main, 130 pilot. I also used the 650 conversion manifold. It started without a prime most days and idled perfect. It had a slight lean hesitation in early spring/late fall that i couldn't get to happen in the middle of summer. It was a Riva powerpomb on pretty much the same setup you got going on now.
shepster
Living the dream!
- Location
- united kingdom, Jersey
Got got a sorted yet Matt ? ?
Curious to know where you ended up
James
Curious to know where you ended up
James
teton
tetongravity.com
- Location
- Washington DC
did you try the full-spectrum on the 61x case motor? if so how did that go
- Location
- New Zealand
I've gone through every carb post and still nothing I can make up my mind with. This is the closest I got to finding out where I want to be...
I have a Single Mikuni 46 on a Riva Manifold, ported cases, Racelogic (squarer) ports job with 8mm sleeve drop, 180psi head, Factory B Pipe with a FX1 chamber and an MSD Enhancer.
Started with a 120L, 150M 2.5N&S 95g spring from my existing setup (minus the port job on the cylinders & skimmed head). Looking at plugs was too lean, so went to a 160M, got a nice brown, went well up high but still never had the balls I thought it should and snap down low (its never had the torque of what i would expect which is why I did the work).
I have moved to 38's because it felt like it wasn't getting enough air either (torque?) and am trying a 75L, 140M, 1.5N&S 95g.. (haven't tried this setup yet - but don't see why I should have to go back to the 38s). I also have a 48mm throttle shaft kit on the way.
Another ski has a Single 48 Mikuni (bored), Riva Manifold, racelogic (Newer trapezoid) ported 760 cylinders, 180psi head, B Pipe with Mod chamber, MSD Enhancer. Has been running a 155M 125L 2.5N&S silver spring.. Appears a bit lean on the plugs up high and doesn't punch as hard as it should...
Can anyone recommend ANY (or all) setup for the aboves using the 38's, 46 or 48s. Both skis are pretty much solely surf skis. We are using the manifold which in the link Matt put up was described as a limiting factor...
I guess what I am after is what pop off pressure do you want ideally for surf? Once I know the pop off I guess that would correspond to the idle (e.g. low pop off small idle high would be bigger?).. Mains we can sort out doing a quick WOT run...
I understand conditions change carb requirements - We are in NZ where the temp goes from 5 deg C to 32 deg C. Riding at sea level (obviously). Any pro input would be GREAT!!
Never had problems sorting out carbs before this!
Cheers in advance..
I have a Single Mikuni 46 on a Riva Manifold, ported cases, Racelogic (squarer) ports job with 8mm sleeve drop, 180psi head, Factory B Pipe with a FX1 chamber and an MSD Enhancer.
Started with a 120L, 150M 2.5N&S 95g spring from my existing setup (minus the port job on the cylinders & skimmed head). Looking at plugs was too lean, so went to a 160M, got a nice brown, went well up high but still never had the balls I thought it should and snap down low (its never had the torque of what i would expect which is why I did the work).
I have moved to 38's because it felt like it wasn't getting enough air either (torque?) and am trying a 75L, 140M, 1.5N&S 95g.. (haven't tried this setup yet - but don't see why I should have to go back to the 38s). I also have a 48mm throttle shaft kit on the way.
Another ski has a Single 48 Mikuni (bored), Riva Manifold, racelogic (Newer trapezoid) ported 760 cylinders, 180psi head, B Pipe with Mod chamber, MSD Enhancer. Has been running a 155M 125L 2.5N&S silver spring.. Appears a bit lean on the plugs up high and doesn't punch as hard as it should...
Can anyone recommend ANY (or all) setup for the aboves using the 38's, 46 or 48s. Both skis are pretty much solely surf skis. We are using the manifold which in the link Matt put up was described as a limiting factor...
I guess what I am after is what pop off pressure do you want ideally for surf? Once I know the pop off I guess that would correspond to the idle (e.g. low pop off small idle high would be bigger?).. Mains we can sort out doing a quick WOT run...
I understand conditions change carb requirements - We are in NZ where the temp goes from 5 deg C to 32 deg C. Riding at sea level (obviously). Any pro input would be GREAT!!
Never had problems sorting out carbs before this!
Cheers in advance..
- Location
- New Zealand
True, but a starting point would help greatly.. I don't mind stuffing about but some advice from experience would save time and mean I could get out in the surf quicker!
I recommend you start at approx. 12psi popoff and find the appropriate jetting combo to work with that. Remember that the pilot jet and the popoff go hand in hand (bigger popoff => smaller pilot and vice versa)
Then work your way up to 35 psi popoff (via springs and/or n/s valves) and find the appropriate pilot jetting for each step.
Once you're done with all that, you'll know what combo worked best.
There is no "ideal popoff pressure for surf". There is an ideal pressure for your setup, and in some cases, ideal pressures for certain carbs (Full Spectrum for example)
You'll have me telling you that IMHO, 24psi popoff works great for dual 44's, while Jared/Waxhead will recommend 12 psi popoff and reverse jetting.
You can take either one and run with it, but.....you'll never know which combo really works best. You can get that only by experimenting around with it yourself.
It takes time, that's a real downer.
IMHO, a single carb should run anywhere from 15-30psi popoff. Lower popoff brings fuel delivery earlier in the RPM curve, but it might dribble fuel when it's not wanted.
Then work your way up to 35 psi popoff (via springs and/or n/s valves) and find the appropriate pilot jetting for each step.
Once you're done with all that, you'll know what combo worked best.
There is no "ideal popoff pressure for surf". There is an ideal pressure for your setup, and in some cases, ideal pressures for certain carbs (Full Spectrum for example)
You'll have me telling you that IMHO, 24psi popoff works great for dual 44's, while Jared/Waxhead will recommend 12 psi popoff and reverse jetting.
You can take either one and run with it, but.....you'll never know which combo really works best. You can get that only by experimenting around with it yourself.
It takes time, that's a real downer.
IMHO, a single carb should run anywhere from 15-30psi popoff. Lower popoff brings fuel delivery earlier in the RPM curve, but it might dribble fuel when it's not wanted.
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