TBE what is it? (Toilet bowl effect) When your Helicopter goes around in a circle pattern with the nose of the heli pointing in one direction. You can not stop from circling even when you try too fly forward or backwards. This effect makes it very hard if not impossible to fly in a straight line and too move at a sustained speed.
How do you get rid of TBE? This is the hard question and I have been dealing with it for years.
TBE seems to come out of no where sometimes, and other times comes from your last crash or from some new parts you just replaced. Here are the things that seem to help the CX/2/3 and most Lama's rid the TBE. If it comes on after a crash then its most likely coming from the new or still bent or broken parts. If it seems to come out of no where, then something changed with out your knowledge. In either case the things to look for are the same and you should have a starting point and take it one step at a time. Here is a list of things to look for and do to get rid of the TBE that makes flying one big HEADACHE!
We start at the top of our Heli at the flybar and upper rotor head and work our way down.
1. The flybar --- if it is bent straighten it out as close as you can, it doesn't need to be perfect. I have flown with very bent flybars and never had TBE from it. But you should have a straight bar for other reason not just TBE. Once you have it straight or have replaced it, make sure it moves very freely and is not getting stuck. Now try a test flight to see if that worked. If not step 2---
2. If you are using the stock upper rotor make sure the little screw that keeps the flybar from flying out is NOT to tight. the flybar must move very freely with no residence. Its ok if their is a little side to side movement. ( Some Lama's have no screw so you can skip this). Also at this time make sure your flybar is balanced. Adjust if needed and test fly----If you still have TBE go to #3.
3. Upper blade tracking. Make sure the tracking is set very close, you should see just one upper blade when running. If it looks like 2 upper blades turn the little rod one half turn at a time to set the tracking. This could be by turning right or left so you may need to try turning it both ways to get the tracking right. NOTE: always wear safety glasses when your doing any repairs of any kind on a running Heli. If needed find someone to help you hold the heli so you can look at the blades.
If you need help you will need 2 pair of safety glasses. Now make a test run to see if the TBE is gone.
If not go to the next step---
4. The upper blades must move very freely. If they are hanging up even a little this can be the cause of TBE. I have been using these little very thin brass washers and have found them too work great. They will keep your blades from hanging up even at high speeds. I always use them now and have cut my TBE problems way down. Test after this fix and if TBE is still there keep on going down the list. Next step-----
5. Check the lower blade tracking. You do this the same way as the top blades. Run your Heli and look to see if the lower blades appear very blurry or look like 2 blades. If it does you have to fix it, unlike the top blades their is no adjustments for the lower. So try new blades and make sure to balance them. If you still have bad tracking you have either a bent outer shaft or a bent or broken lower rotor. Start by taking off the blades and run just the outer shaft to see if its bent. Even a little bend can make for a big tracking problem and shaking. If bent replace it and try your Heli. If you still have bad tracking even after replacing the outer shaft then the lower rotor most likely is bent or broken. A break is easy to see in most cases, but a slight bend is not, so you will have to replace it to make sure. Your tracking should be fixed now and you can test for TBE. If you still have TBE your getting down to one thing that a lot of people over look.
6. The swatch plate. It can come apart in a crash and it is very hard to see. Just take it and push it back together, if you hear it snap it was apart. Also I have had some CNC swatch plates cause TBE, so go back to stock and see if this helps.
7. Defective new parts. yes this happens and it can be just the part that is making your heli go into a TBE fit. I once had a brand new lower rotor and started getting TBE after I installed it. I put the stock one back on and the TBE was gone. So if you just finished putting some new CNC parts on and TBE starts try going back to the stock parts to see if it helps.
8. Bad motor or motors. If you fly everyday like I do the motors will go bad faster than you may think. most of the time you will be fighting a lot of tail drift from right to left, or the Heli spinning in a circle. If your motors are going out you need to get new ones TBE or not. I once fried a 4 in 1 by flying with a bad motor. When the motor finally froze up my 4 in 1 fried because I didn't shut down the heli fast enough. $59.00 hurts a bit so keep good running motors on your Heli at all times. Stock motors are fine but their are some aftermarket ones out that are much better for a few dollars more.
9. Make sure to take your time and inspect all the parts very close. Sometimes you have too look at a part 2 or 3 times before you see the break or notice it has a slight bend.
I know just how hard and frustrating it can be to find what is giving your heli TBE. But if you take it one step at a time and follow this list you should be able to get rid of this problem in a few minutes and get back to having fun flying once more.