[Adrian II]

The Dell'Orto PHF 36 is an excellent choice, two of my REs (neither of them CGT or previously EFI) have them. I would be interested to see a note of your needle and jetting set-up if it's not a state secret.  You can buy Italian one piece flanged carb rubbers from Malossi or Ariete for the PHF with the necessary 60mm stud centres for ease of fitting.

You might have found that the issue with going up to a Dell'Orto PHM38 is simply the extra bulk and fitting concerns compared to the PHF range, rather than any performance issue. There's a Paul Henshaw video on You Tube of a 500 RE Fury being ridden quite happily around a variety of Welsh roads from lanes to main road with a 38mm carb fitted, though it's an Amal rather than a Dell'Orto.

A.

[Adrian II]

And here's a sales picture of the PHF36. You will have noticed from Noddy's second picture that polished alloy bellmouths up to (70mm long) are available too.

A.





Photos: www.dellorto.co.uk

[Taurim]

Hi guys,
I'm gary from Leicester in the U.K.. I have just come across this forum, and found this thread of great interest. I too have a 535GT (2015) and I also bought it to modify. Around 3 years ago I built my own flow bench to enable tuning the cylinder head. I have many years of tuning experience, so bought a brand new head from India and set about making improvements to the flow of 'gas' in and out of the cylinder head. I had done all the other usual stuff, larger valves, higher lift longer duration cams and of course, the outrigger bearing plate to support the crankshaft outside of the alternator. The handicap to producing good power was the fuel-injection system. I did have a power commander fitted, and with all the work done the bike felt strangled at high revs. The only way to go, was to fit a carburettor, replacing the fuel injector. I went for a 36mm Dellorto 'pumper' carburettor, having had much experience with them on Ducati race motors. I suspected a 38mm would be just too much, and lead to poor pick up and torque in the lower rev range. I kept the Power Commander V, not for the fuelling, but to allow switchable ignition curves and add the 'rev extend'  feature. The bike will genuinely do over the 'ton' now, without a fairing, and with me in a racing crouch. In the attached photos you can see the carburettor, and below the carb is a rotary switch to change the ignition advance curves (while road testing). I think a better piston would help produce even more power, but at the time I could not find anything suitable - perhaps there is something available now ?

Hi Gary. Welcome here 

You should read my thread. More than the ton is possible with the injection  (did 165 kph at the GPS : https://www.youtube.com/watch?v=8k2PjlxD66w )
About the injection or carb diameter Derottone machined his injection throttle body from 34 to 36mm and I'm about to do the same 
H's now sells flat top forged piston.

My thread: https://forum.classicmotorworks.com/index.php?topic=29864.0

[StreetKleaver]

About the injection or carb diameter Derottone machined his injection throttle body from 34 to 36mm and I'm about to do the same 
H's now sells flat top forged piston.

I agree Taurim. Depends what you're trying to achieve and what you're comfortable with.

I come from a motocross and enduro racing background. Most of my race bikes ran Mikuni Carburetors. So that's what I run on my Iron Barrel 535, I have loads of jets and spares . A Mikuni VM32, matches the intake port size. Looks period correct and functions really well for the the bike. I could of gone a TM flat slide Mikuni. Possibly got better throttle response and better economy with that carburetor . But would of been very minimal due to the engine design.

But with my GT535, I'll be sticking with the Fuel Injection and Power Commander V. Locally I have a Dyno Tuner that can easily tune the bike with power run and have that luxury of fine tuning every aspect that EFI has to offer. More effectively compared to hours plug chops and ride tuning it takes for me to fine tune a carburetor.  But I still enjoy doing either!

[Arschloch]

I am not sure EFI is easier to tune or let´s say adjust than a carb, especially when you have to pay for the dyno operations. Than you could get an autotune device which will react to any mods you do to the engine and you do not have to book hours of dyno tuning. Than again that device costs, a carb is probably bit of self adjusting once a correct AFR is set kind of like a EFI+PCV+Autotune in one device. Engine power stays unimpressed of either device, efi or carb.

I will go carb if should I decide to do further mods to the engine.

[StreetKleaver]

I am not sure EFI is easier to tune or let´s say adjust than a carb, especially when you have to pay for the dyno operations. Than you could get an autotune device which will react to any mods you do to the engine and you do not have to book hours of dyno tuning. Than again that device costs, a carb is probably bit of self adjusting once a correct AFR is set kind of like a EFI+PCV+Autotune in one device. Engine power stays unimpressed of either device, efi or carb.

I will go carb if should I decide to do further mods to the engine.

I have a laptop sorted with Power commander software. My local Dyno guy takes an hour or 2 tops to get it sorted. Shove a "sniffer" (AFR sensor) down the exhaust, few power runs. All with the luxury of making adjustments on the laptop. Unlike trying to find a road with no traffic to do plug chops and fumbling with a hot engine and carburetor. Which don't get me wrong, I enjoy doing and it's what I learned first. But some days I run out of daylight and spark plugs getting it just right.

It's nice to have that luxury of both. Unfortunately no one around my area wants to Dyno tune with Carburetor bikes anymore due to the added time and how fiddly they can be. I have to take the bike 4hrs south for that. They'll only touch programmable EFI motorcycles. 

[Taurim]

I did all the setup by myself while riding with the PCV + the Autotune module and a Lambda wide band permanently attached to the exhaust header.
It's very practical and fun to use. I described everything in my thread.

I won't say it's a better option than a carb because my bike is Euro 4 and the PC V can't have so much control on the injection map than with a Euro 3 ECU.
But it's working perfectly except some hiccup around 3.5K when re-accelerating. I hope to find a solution for that one some day.

Installing a carb would have been too easy 

[StreetKleaver]

Little update. Clubman bars and my favorite "foamies" grips. When the fork gators arrive I'll be stripping the Triple-clamps, sand blasting and painting them 2k gloss black.







Next is to fabricate up some brackets and bushes and do something about that big honky rear light assembly. Very much similar to my Bullet, yet different.

[Taurim]

I replaced the rear light with a so called "Mini Lucas" you can easily find on eBay.
It's not a direct fit and requires some modifications but I find it a lot nicer than the HUGE standard light.
I also attached it with some rubber grommets to try to limit rear light bulb consumption.

[Arschloch]

I went with the mini Lucas too. 

The clubman bars fit like a glove to this machine. 

[StreetKleaver]

I've got a round miller style light to go there.

I'll be attacking that rear hoop with my grinder, shortening it by 50mm and TIG welding up a few bits here and there. It will be neat and thought out similar to my Bullet in aspects.

There will be a bit of rear guard left. But not much, a lot of it is going to be scribed off. Standby for updates. 

[StreetKleaver]

If you know of my other Iron Barrel Build, nothing really stays the same for long. I chopped the rear hoop off. Shortened it. TIG'd it back on.

Hoop chopped.


Shortened and tail light mounting section. Bit of flat bar with stainless weld nuts behind it. Got all dressed up and smoothed off.



Tail light trail fit.



Fully welded out with the TIG and started to scribe out the guard. It will sit tucked up under the seat and flush with the inside of rear hoop.
The seat mount cross member bracket was also relocated and I actually corrected it's dimensions. It was 2mm out of square and 3mm difference in height left to right.



Thats enough for a Sunday. More to come soon.

[StreetKleaver]

A little more progress. The weather has been woeful so I couldn't get any paint down today.

Forming up the new number plate bracket.



Rear hoop finished. Few coats of high fill ready for a light hand sand and feathering.



And a handful of parts in primer ready for paint. You'll notice the rear guard is shorter. It tucks in nicely behind the rear hoop. All will see it when it's finally assembled again.

[gizzo]

Nice work!

Where did you buy that vice mounted sheet metal folder? I didn't know that was a thing but I need it.

Using the work issue Hi Vis as paint masking: that's such an Aussie thing to do 

[StreetKleaver]

Nice work!

Where did you buy that vice mounted sheet metal folder? I didn't know that was a thing but I need it.

Using the work issue Hi Vis as paint masking: that's such an Aussie thing to do 

They've been around for a while. I've even banged a hinged folder up for a old work bench.

Thats a 125mm one, got it from Jaycar of all places. Supercheap have Kingchrome 100mm and 125mm ones.

I use it for lots of little brackets and bits and pieces.

I have more Hi-Vis work clothing that I have normal clothes! 🤣 And with the reflective strip's and being 100% cotton drill they aren't much use for rags. So throw em over things for spark or paint protection. Haha