54mm throttle bodies

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blinkey501 · #16 Post by **blinkey501** » Mon Aug 05, 2013 5:13 am

I am looking forward to getting the bike sorted.
I will of course post the details of what happens with the chip fitted.
I tried the 54's on the stormtrooper and it was lumpy.
The throttle response was all or nothing. And you had to wait a second or two for the bike to respond.

D-Rider · #17 Post by **D-Rider** » Mon Aug 05, 2013 9:36 am

Not what I got at all with mine Jay. Sounds like a set-up problem.

Smooth and easy to ride - just that the tick over couldn't be reduced .....

wannesd · #18 Post by **wannesd** » Mon Aug 05, 2013 9:52 am

D-Rider wrote:Not what I got at all with mine Jay. Sounds like a set-up problem.

Smooth and easy to ride - just that the tick over couldn't be reduced .....

Perhaps the butterflies?

D-Rider · #19 Post by **D-Rider** » Mon Aug 05, 2013 10:12 am

Yep that's my diagnosis - hoping to get some new ones made up

wannesd · #20 Post by **wannesd** » Mon Aug 05, 2013 10:14 am

Haven't really looked into TB's, so may be completely off, but:

as far as I understand, only 51 and 57 were actually produced, and the 54's are bored out 51's? Why not go 57 and have perfect butterflies instead of going 54 with all the trouble that seems to be involved?

D-Rider · #21 Post by **D-Rider** » Mon Aug 05, 2013 11:17 am

Yes only 51mm and 57mm were made.

54s (and even 55s) are just bored 51s. They require an accurate uniform bore, reworking of the air bypass channels and very accurate new butterflies.

The reasons for 54s as opposed to 57s are that the 57s really give no benefit over the 54s and (according to Gabro and others) don't work as well on Falco and Gen1 mille engines as 54s.
The fuel injectors also require different connectors - so link harnesses need to be made up.

The benefit of 57s is that their butterflies fit properly.

So for an easy fit (other than the connectors) 57s have their advantages - however, well made 54s are a more optimal solution for our motors.

wannesd · #22 Post by **wannesd** » Mon Aug 05, 2013 11:19 am

Thanks for clarifying!

Now, I don't think TB's are necessary on my setup (k&n filter, shortened leo's and a gabro chip), but maybe in teh future...

Where can you acquire the parts, and have the machining done? Or are there kits available of some sort?

D-Rider · #23 Post by **D-Rider** » Mon Aug 05, 2013 11:22 am

Evolusione in the USA used to do them.

Basically you either have to do it yourself (there is a lot of good info scattered through innumerable threads on the AF1 site) or wait until a set comes up for sale (and hope they have been well made)

HisNibbs · #24 Post by **HisNibbs** » Mon Aug 05, 2013 2:52 pm

I have gone down an alternative path and fitted a quick action throttle. Much the same effect as larger throttle bodies without any setup problems, probably cheaper too.

D-Rider · #25 Post by **D-Rider** » Mon Aug 05, 2013 3:15 pm

Yes I've speculated that this may give a similar effect but Gabro and others seems to say there are other advantages ..... though I'm not really clear what these might be (other than at full throttle - which is a rare situation)

Millsy · #26 Post by **Millsy** » Mon Aug 26, 2013 11:27 pm

Little tip.......Honda SP1 uses 54mm throttle bodies,so I guess you could use butterflies from those......simples.

D-Rider · #27 Post by **D-Rider** » Tue Aug 27, 2013 8:56 am

Interesting
Could be worth looking at - though I suspect the devil will be in the detail (and will depend very heavily on how accurate the 54mm bores are - the problem is probably more of a matching thing)

Nevertheless an interesting suggestion ...........

D-Rider · #28 Post by **D-Rider** » Tue Aug 27, 2013 2:54 pm

jonnie_r wrote:Definitely not riding it. Just gave it a quick start to see if it was ok.

Will be loaded in the van first thing and carted to the dyno for PC3 install and set up.

Well ............. what happened?

Is it all running sweetly with the 54s ?

paddyz1 · #29 Post by **paddyz1** » Tue Aug 27, 2013 8:04 pm

Aladinsaneuk wrote:I got my 54s off paddy who had exactly the same symptoms ....

For a very cheap price

He was well pissed when I told him how I adjusted it...

It may just be coincidence but

Err, no I wasn't. I got what I wanted.
As for the 54's, there was no point in them IMO, apart from an 8hp increase in the midrange and the rest was at the top end (how often are we going to ride at 150mph+) I just twist the throttle a bit more to get the same result. Also they needed the power commander which smoothed everything out but that meant the bike lost its soul so I took it everything off and now it runs on its own raw power which is perfect for my riding style.

Aladinsaneuk · #30 Post by **Aladinsaneuk** » Tue Aug 27, 2013 8:21 pm

Paddy power ;)

It's the mid range I like - and we were both happy with the outcome