Twinmax - Help, please!

[Psyko]

Just bought a Twinmax. Have adjusted the valve clearances on my 1150 and moved on to balance the throttle bodies. I removed the small black rubber covers from each throttle body nipple and then went to connect up the two Twinmax tubes. The internal diameter of the tubes is slightly wider than the outside diameter of the TB nipples. Thus the tubes slide over quite easily without having to be pushed on. Instinctively, this doesn't seem right as air could be sucked in around the edge breaking the vacuum - if I understand correctly how it works.

The Twinmax comes with some threaded nipples for use on bikes without built in TB/Carb nipples and the tubes have to be pushed onto these - indicating that this is how tight the tubes are meant to be.

Am I right in thinking that the tubes are too wide - or does it not matter (perhaps becuase the TB sucks the tube into a tight seal when the engine is on??). Or am I doing something really obviously stupid (wouldn't be the first time!).

Anyone else had this problem or do your tubes fit on tightly? If so, do I need to get new tubes? The Twinmax also comes with two very small (rather crudely cut) pieces of thinner, clear plastic tubing - I did fiddle around with these but couldn't see how they would help as they are too narrow to go over the TB nipples and don't fit snugly into the Twinmax tubing.

Any help or guidance would be much appreciated ,

Thanks,

Psyko

 

[cookie]

tighten the fit with a small zip tie around each tube over the nipple

 

[welder8uk]

All I did was get some small diameter water pipe (ie the type from an aquarium/ from halfords for car windscreen washer systems, the clear plastic stuff) and just push them on the inside of the pipes that come with the Twinmax (if I remember correctly I superglued them in to form a good seal). They might have been the two pipes that came with it, I cant quite remember it was a while ago.

You'll need some of the pipe anyway 'cos them stupid black plastic nipple end things will break and need replacing. So I just got a bit of the small diameter pipe, blocked the end with a small section of a thin bolt and pushed the other end on the nipple.

Again, if I remember correctly I superglued them in to form a good seal.

Easy

steve

 

[jkersh1]

In addition to the two long sections of tubing, my Twinmax came with two short sections of the proper diameter tubing, and connecting step-down adapters.

 

[Den]

The wee bits of clear plasic tubing DO fit on the nips and the twinmax tubes fit over the top.
Its a bit of a pain trying to get the clear tubing off the nipples when you have finished.

 

[Psyko]

Thanks

Thanks for the advice and tips - this forum comes up trumps as usual!

I'll have another go.

Cheers,

Psyko

 

[Psyko]

Success - I think!

Thanks for the earlier advice - I had a bit of unused marine fuel pipe that I cut into identical lengths. One end pushed tightly onto the Twinmax tubes and the other end pushed neatly onto the TB nipples. Job done!

Next query. When I balanced the TB's - which I think I have done - I followed the "Throttle Body Synching for Dummies" (23rd September 2003 version). A great document with clear instructions and good detail. However, in order to adjust the TBs, I eventually found that I had to do EXACTLY THE OPPOSITE of what is suggested I can follow the logic of what they recommend - i.e. increasing/decreasing the length of the throttle cable to adjust the butterflies etc. but it seemed to affect the read out in the opposite way!

Do you think it is possible the the Twinmax is "cross wired" internally so that the cylinder readings are the wrong way round? Even as I type this I am wondering if I misread the instructions - but when I think carefully, I am pretty sure I didn't.

Anyone else come across this? I suppose it's not a big deal once you know how to get the balance right. The final readings were at Zero at both Min and Max sensitivities at idle and at 3.5k revs.

I'll take the bike for a run this afternoon and see how it feels.

Cheers,

Psyko