how to lighten a LOOP FRAME throttle?

[lazlokovacs]

the throttle action on my v7 750 speciale (euro version of the ambassador) is too stiff!!!

I ride long, long, long days.

compared to my old triumph (1969 T100) the throttle action is ridiculous.

The triumph has a single AMAL.

The Guzzi has 2 dellortos.

Somewhere on thisoldtractor there is a link to some people who fitted single carbs.

Has anyone here tried this? Does it actually work?

Or any other ways of getting those Dellortos to give you less of a pain in the wrist/forearm??

I've got a no-name throttle and an upper cable going into a splitter box setup.

[guzzisteve]

Try lube & grease in the splitter and make sure cables are not twisted, grease on handle bar tube too.

[Triple Jim]

I put lighter springs in my Mille's carbs without negative consequences.  Maybe lighter springs are available for yours.

[Antietam Classic Cycle]

The "no name" (actually made by Magura) throttle was never one of my favorites. Try what Steve said - make sure everything is well lubricated and the cables are routed so there are no sharp bends.

Some folks have had luck using lighter slide springs:
http://www.mgcycle.com/index.php?main_page=product_info&cPath=62&products_id=4661
but on a few bikes I've put them in, the rpms would "hang" and not drop back to idle properly.

You could try a Tommaselli 2C throttle and dual cables.

Maybe try some larger diameter handgrips as well.   

[danedg]

The Tommaselli 2C(able)throttle eliminates the splitter. And provides a positive stop for the big road...

[brider]

I use the larger-diameter Harley-style grips with the chrome ribs and it really does make a difference. Even still, my old Eldo with the Tomaselli 2C throttle was still a lot stiffer than my Cal 2 with the round slides. Wonder why?

[jacksonracingcomau]

Johnny
What he said but
Tomaselli throttle, two venhill cables and lighter springs
I did a loopy last year, one of issues is getting routting (sic) right for cables to go under tank with no kinks. Buy venhill featherlight diy kits, silver solder nipples, that�s then as good as it gets should be same as any bikes with 2 vhb carbs. One I did was night and day from how it was.
Good cables don’t hang
Did you get the Cali sussed ? Expected to see you in London, maybe next summer ?

[Antietam Classic Cycle]

I use the larger-diameter Harley-style grips with the chrome ribs and it really does make a difference. Even still, my old Eldo with the Tomaselli 2C throttle was still a lot stiffer than my Cal 2 with the round slides. Wonder why?

Because the spring in a VHB pushes the slide forward against the carburetor body by design - that's how the square slide seals against the body. In the PHF, the spring just pushes straight down, not down and forward. Less friction.

[mtiberio]

The springs in my Chinese PWK carbs on my Eldo are so light it feels like fuel injection...

my conversion uses an Amal manifold, easily found for Guzzis since no one wants the Amals. However, Amals just might have a lighter spring as well, and since they are still manufactured, and from what I hear better than they were back in the day, it might be worth a look.

http://wildguzzi.com/forum/index.php?topic=84861.msg1338434#msg1338434

[brider]

The springs in my Chinese PWK carbs on my Eldo are so light it feels like fuel injection...

Sent you a PM about those carbs.

[bigbikerrick]

A tomasseli 2c throttle, new cables, and lighter springs did the trick for my eldorado. Getting rid of the splitter was one of the best things I did. I have  had no problem with the slides sticking at all.
Rick.

[mtiberio]

here is a thread I started 8 years ago. I'm still running these carbs...

http://wildguzzi.com/forum/index.php?topic=29772.msg452500#msg452500

[lazlokovacs]

thanks everyone

^mtiberio^ thanks for the link, do you think I could still run the stock airbox with the PWK carbs?

^^martin^^ I'll drop you a line, chat soon

[lazlokovacs]

ps Martin,

Venhill cables look good,

you mean something like this?

https://www.venhill.co.uk/cables-amp-components/universal-cable-kits/throttle-cable-kits/u01-4-100.html

[jacksonracingcomau]

ps Martin,

Venhill cables look good,

you mean something like this?

https://www.venhill.co.uk/cables-amp-components/universal-cable-kits/throttle-cable-kits/u01-4-100.html

Yeah but they used to supply ss inner with featherlight kit, now gal, worth a call but gal easier to solder, ss needs silver solder and more heat. Gal is a doddle, electric solder works fine.

[wicks]

Did Venhill cables, lightest Dellorto slide springs, and cleaned / lubed the grip tube and housing with liquimoly. Featherlight throttle now on LM with all stock PHF 36s. The Venhills aren't perfect, the end fittings are too small thus they won't stay straight in the Tommaselli housing, and don't fill the carb levers cutouts, but they work.

Perhaps Venhill has a staffer who is on this board sometimes and they can be given better specs.

[Furbo]

Biggest secret is Teflon lined cable.

See Venhill provides that. I bought a bunch of it for throttle & clutch cables as well as a variety of ends from Barnett directly 2 decades ago and haven't bought a cable since.

Routing - no kinks or hard bends

Clean - the throttle body, inside the hand grip tube, and where it rotates. The splitter (if you have one). Get it spotlessly clean.

Bar - if the bar has paint - get it off. Sand the bar with fwd/reverse motion like you'd shine a shoe. work down to a fine grit paper.

Lube - lube the splitter and the throttle with powdered graphite. The graphite will 'fill in' any remaining rough spots on the bar and not attract dust like grease will.   

Springs - lite springs are fine as long as the rest of the system is free.

[Cam3512]

I know this is an old thread, but I’ll offer up this.  Stock carb springs are heavy, 2 kg.  The light springs MG Cycle sells are 1.1 kg.  When I tried the light ones in my former Eldorado, the slides would get hung up.  I found a few sets of MEDIUM springs, 1.5 kg.  They were the perfect fix, and I have them in my Ambo and V7 Sport.  Hard part is finding them.  I recall MG Cycle at some point offered them for sale?

[mtiberio]

there are Amal manifolds from late Eldorados/GT850s which should fit your bike (kinda). Get a set of those, and you can run either Amals or a set of chinese clone PWK Keihins fitted with amal flanges. throttle action like FI.
https://www.ebay.com/itm/Carbs-TRIUMPH-NORTON-BSA-Amal-930-alternative-PWK-30mm-carburetors/362710256596

[Antietam Classic Cycle]

The springs in my Chinese PWK carbs on my Eldo are so light it feels like fuel injection...

my conversion uses an Amal manifold, easily found for Guzzis since no one wants the Amals. However, Amals just might have a lighter spring as well, and since they are still manufactured, and from what I hear better than they were back in the day, it might be worth a look.

http://wildguzzi.com/forum/index.php?topic=84861.msg1338434#msg1338434

there are Amal manifolds from late Eldorados/GT850s which should fit your bike (kinda). Get a set of those, and you can run either Amals or a set of chinese clone PWK Keihins fitted with amal flanges. throttle action like FI.
https://www.ebay.com/itm/Carbs-TRIUMPH-NORTON-BSA-Amal-930-alternative-PWK-30mm-carburetors/362710256596

[geodoc]

In addition to what's been mentioned re: nylon lined cables, etc., I really like Throttle Rockers. I have carpal tunnel in my right wrist and this really helps:







.

[Antietam Classic Cycle]

In addition to what's been mentioned re: nylon lined cables, etc., I really like Throttle Rockers. I have carpal tunnel in my right wrist and this really helps:







.

I have "Fin-Q" grips on my Convert and they really help. Partly the barrel shape and soft, grippy rubber, but mostly the "fin".

[Tom]

It doesn't hurt to lightly lube the slides and the carb body.  Biggest results were from rerouting the cables and lubing them. 

[Turin]

Who sells Fin-Q grips?  I've been looking for a set for my 850T sport. Years ago I had a set on my Alazurra and loved them.

[Antietam Classic Cycle]

Who sells Fin-Q grips?  I've been looking for a set for my 850T sport. Years ago I had a set on my Alazurra and loved them.

While searching for the photo above, I found "Dixie International" that appears to be a distributor of parts, but never did find a retailer with them. IIRC, Harper's did have them, so it might be worth checking if they still do. I was fortunate enough to be given several NOS pairs by the late Bill Sharp.

http://store.dixieinternational.com/index.php?route=product/product&product_id=7250

[geodoc]

In addition to what's been mentioned re: nylon lined cables, etc., I really like Throttle Rockers. I have carpal tunnel in my right wrist and this really helps:




.

As an aside, one advantage on the throttle palm rest like above is that you can change it's relative position on the twist grip on the fly. So if you're cruising along in a 40 MPH stretch it will be in a position where it's most comfortable v. cruising at 75 MPH and you can rotate it to suit. I found mine would slip a little over time, but wound a little hockey stick handle tape on the grip and then the rocker over it to fix it more solid.





.

[wicks]

Adding some additional experience here. Venhill asked me to send back their cables AND my original cables, so they could study. I am declining - that would leave me with no cables. I had offered to send them my original cables to re-engineer the end fittings etc. Oops.

RE SPRINGS: I ran the lightest (there are Stock, Medium and Light available), but if you run the revs up, the light springs are not strong enough to close the slides with that much air being sucked in even with the grip closed, so they will hang open a bit. You can shut them all the way with a blip on the grip, but this setup makes your engine braking vary, which is disruptive. The lower the revs, the more easily the slides will close of course, and they will eventually close on their own, but I'd rather have consistent engine braking to manage along with trail braking the front (hand brake) caliper to improve cornering geometry and stability.

I moved to Medium springs, and the throttle remains very light (with the grip housing and tube very clean and lubed with moly, and the Venhill cables installed and routed nicely) and the slides close properly even from high revs.