Vibes Galore !

[Rusape]

I've recently added Remus headers (decat) and and Akra pipe to my TC GSA and have noticed a considerable increase in vibes, across the whole rev range.

The bike picks up noticeably quicker and does feel much more lively.

I've been following the Hilltop remap thread and guess the obvious route would be a remap but before I do so however, has anyone experienced the same problem, that a remap actually sorted??

Didn't think I'd get this much more vibration from just changing the pipes. They are installed correctly with nothing touching the frame or body.

 

[oblertone]

You've ...

... left a 12mm spanner on top of your bashplate

 

[Bendy toy]

Does the OP mean vibration as in numb hands or just noise/buzz? If the latter make sure the bash plate isn't shaking loose.

I have an Akra system on my GSA and do have a problem with handlebar vibration. But it was always there. It's not got worse with the new exhaust system. I have a cross brace and Rox anti-vibe risers but they dont smooth it enough to suit my poor hands. TBH the Rox were excellent on an 8V inline four, but nothing special on the single cam 1200GSA.

I'm working on designs for sorbothane mounted handlebar clamps and some sorbothane grips.

 

[Mr K]

Slacken everything off and re-tighten (on the exhaust).

 

[Spout]

First things first - valve clearance check and throttle body balance.

 

[Bendy toy]

Done that but made zero difference. No surprise, because it vibes no worse with the Akra then it did with the standard system.

The engine runs lean as standard, but the ECU can cope with a free flowing exhaust, but not with a K&N filter AND free flowing exhaust.

 

[Rusape]

Does the OP mean vibration as in numb hands or just noise/buzz? If the latter make sure the bash plate isn't shaking loose.

No the bike has become much more "lumpy" from tickover, through the rev range,

It's now like a Harley when at idle, cant see through the mirrors !

Something me thinks is not quite right... unless this is what normally happens with a decat and Akra .

 

[Bendy toy]

When mine did that it was a plug or coil problem. I took out all the plugs intending to test the coils but the multimeter prods wouldn't reach. Put it all back and its been fine ever since.

 

[fringe]

standard can also has a rubber mount insert on the twincam (where the bolt goes through), whereas the akra just bolts direct to the frame, so no slight damping from the end can anymore....

 

[Bendy toy]

My Akra has a rubber mount under the gearbox. The cans are solid bolted to the frame. But there are no signs of distress and the engine is solid mounted so really it should be ok. That said the Akra joints are all slip-fit with retaining springs and high temperature antiseize on the pipe joint surfaces.

 

[fringe]

My Akra has a rubber mount under the gearbox. The cans are solid bolted to the frame. But there are no signs of distress and the engine is solid mounted so really it should be ok. That said the Akra joints are all slip-fit with retaining springs and high temperature antiseize on the pipe joint surfaces.

Granted the frame is bolted to the engine, but the springs and slip on fitments will only take up any movement due to weight of the exhaust system under acceleration/braking.

But any frequency thats going through the actual pipework will not be taken up by the springs and slip on connections, instead vibrating through the material and now onto the frame, as oyu ahd two damping points before, now you only have one under the gearbox.

I have noticed more vibration after just attaching the akrapovic over my standard can, back to back.

 

[Bendy toy]

I will have to try a rubber grommit on the Akra silencer clamp. But as the exhaust pulses are running at the same rate as the engine is turning and the engine is solid mounted, I dont expect much change. There is zero speed difference so there can't be any harmonic interference.

BTW, I now have some Sorbothane to start working on my anti vibe handlebar mount.

 

[blues n twos]

I think I would be tempted to put original end can back on and see how it runs and work back from there.

If it runs sweet you know it's the end can. Also try original headers with Akro etc.

Jon

 

[Rusape]

No more vibes

Well I took the bike to Hilltop today for a remap.

The figures , like everyone else so far, show a substantial increase in BHP from 83 - 104 bhp and 66-81ft lbs tq.

The bike does indeed feel more punchy, but there is defo not a 20% increase in power as the figures may suggest... what I do have is a super smooth (for a boxer) bike again and no more vibes.

Was it worth it???

Belting with rain on the way back so couldn't push it too hard.. Time will tell.

 

[Beemerman59]

The figures show a substantial increase in BHP from 83 - 104 bhp and 66-81ft lbs tq.

The bike does indeed feel more punchy

but there is defo not a 20% increase in power as the figures may suggest

Belting with rain on the way back so couldn't push it too hard.

 

[Rusape]

Tried to cure the bad vibes after fitting Akra and headers, but nothing worked, so took bike to get remap as I figured the fuelling was out. No more vibes after the Hilltop remap.

Yes I realise the Hilltop info was off topic, but added it anyway expecting most to make the connection with the vibes bit.

 

[Beemerman59]

Tried to cure the bad vibes after fitting Akra and headers, but nothing worked, so took bike to get remap as I figured the fuelling was out. No more vibes after the Hilltop remap.

Yes I realise the Hilltop info was off topic, but added it anyway expecting most to make the connection with the vibes bit.

Its what you said that I couldn't make sense of. You say the Dyno results show a significant increase in performance and that the bike feels more punchy. You then said it doesn't equate to a 20% increase (despite the Dyno figures saying otherwise and your own feeling of punchiness) and then you said it was wet on the roads so couldn't push it very hard (so how can you tell anyway). A bit contradictory as I read it.

 

[Daffy]

I started reading this thread and thought he needs a remap to sort this, I have Remus headers and a std silencer (I took the Akro off) and my hands were going numb after about 20 miles at motorway speed.

The hilltop remap completely sorted this, I took it to work today (120 mile round trip) and forgot about the remap but soon realised that it was smooth as silk.


Recommended from me also.

 

[Bendy toy]

I have run standard system, Remus headers with standard silencer and Akraprovic "race" Ti system with twin cans. Vibrations are all the same, though eh Akra"feels worse because it gives more midrange punch so I'm pulling more on the vibrating handle bars.

To my mind the solution is some anti vibe bar mounts (not Rox they miserably fail to work on the GS). I will also be getting a remap but don't see how it can change the mechanical facts of life in the boxer engine.

 

[Pukmeister]

I will also be getting a remap but don't see how it can change the mechanical facts of life in the boxer engine.

It's not the mechanical parts themselves, its the way they respond to better controls strategy from the remap (fuel/air ratio and ignition under both load/acceleration and steady throttle).