MIK4455 Logo 500/600 Aluminum Drive Pulley

[taosgraveyard]

the parts that this aluminum upgrade replaces (MIK4089) come with 4 spacers, 2 for each shaft of the two belt tensioner one spacer goes above the pulley and one below, on the pulley shaft

the upgrade comes without any spacers

so.... do I put MIK4455 in as is, or use the spacers from the original parts?

seems weird if the spacers are required for mikado not to include them, since they DO include with with the original plastic parts

[BTB]

Originally Posted by taosgraveyard

the parts that this aluminum upgrade replaces (MIK4089) come with 4 spacers, 2 for each shaft of the two belt tensioner one spacer goes above the pulley and one below, on the pulley shaft

the upgrade comes without any spacers

so.... do I put MIK4455 in as is, or use the spacers from the original parts?

seems weird if the spacers are required for mikado not to include them, since they DO include with with the original plastic parts

You have to use the spacers that came with the plastic pullys in your kit. Do not put the pullys in as is..

[taosgraveyard]

Originally Posted by BOBTHEBUILDER32

You have to use the spacers that came with the plastic pullys in your kit. Do not put the pullys in as is..

thanks - got the calipers out and just figured that out...

of course the reason i bought these is because the one of the ones that came in the kit failed (after about 6 flights), ruining the pulley AND the spacer, breaking the belt, crashing the heli HARD...

So now i have to buy a set of the stock pulleys, just to get the spacers...

sheesh.... the spacers come with a set of the stock pulleys, but not with the upgrade? what are they thinking??? they call the set complete in the write up too...

[motorcycleguyr1]

that sucks, how did they fail exactly? anyone else have reports of this?

[zguy]

I've experienced failures also and know of another owner who has had multiple failures.
Is yours a 500 or 600? These failures are on 500's.

[BTB]

Originally Posted by taosgraveyard

thanks - got the calipers out and just figured that out...

of course the reason i bought these is because the one of the ones that came in the kit failed (after about 6 flights), ruining the pulley AND the spacer, breaking the belt, crashing the heli HARD...

So now i have to buy a set of the stock pulleys

Did you secure the pulleys in the frame tabs with shoe Goo to keep them from popping out. I didn't have to put much force on mine to get them to pop out of the plastic frame.

[taosgraveyard]

Originally Posted by zguy

I've experienced failures also and know of another owner who has had multiple failures.
Is yours a 500 or 600? These failures are on 500's.

A 500

My 600SE has been fine

[taosgraveyard]

Originally Posted by BOBTHEBUILDER32

Did you secure the pulleys in the frame tabs with shoe Goo to keep them from popping out. I didn't have to put much force on mine to get them to pop out of the plastic frame.

That's true, not much force.
Shoe goo, huh. I happen to have some.

So do you just put some in the slot that the pulley shafts snap into? Top and bottom? Make surer it does notc get on the pulley bearing?

Simple fix...

?

[BTB]

Originally Posted by taosgraveyard

That's true, not much force.
Shoe goo, huh. I happen to have some.

So do you just put some in the slot that the pulley shafts snap into? Top and bottom? Make surer it does notc get on the pulley bearing?

Simple fix...

?

It should be a simple enough fix. I got the idea when I saw the finless bob logo 500 build videos. I didn't do it to my plastic frame, but I did use some to keep the pulleys from spinning in the metal retaining blocks in the cf frame. I can't remember if bob shows how its done in the first or second build vid so I will post both.. yes you should put some Goo in the top and bottom tab, as expensive as those little bearings are I would try my best not to get glue in them.

http://video.helifreak.com/?subpath=...p1a_frames.wmv

http://video.helifreak.com/?subpath=...p1b_frames.wmv

[zguy]

Originally Posted by taosgraveyard

A 500

My 600SE has been fine

There is a geometry issue where the belt is riding on the lower lip of the LH guide pulley.

I've had two crashes caused by this failure and replaced both side frames and booms each time. Even if something was off/bent in the first, what caused the second with all new parts? BTW-the frames did not break in either crash, but rather were gouged out on the inside by the belt when it came off the guide pulley both times.

I'm now using the metal guide pulleys and the belt is still riding on the lower LH lip. I can remove the shims to bring the drive pulley upward, but it only makes the belt ride to the low side of the drive pulley and does not bring the belt off the lower lip of the guide pulley.

I have no idea why this appears to be effecting 500's vs. 600's

If anyone else has had issues, or even better a solution please chime in!

[OverTemp]

I think the main shaft bearings seat slightly differently in each frame set. They continue to seat for the first couple flights.

The spacer locations in the manual are good starting points, but I've had to adjust the locations and thicknesses on all 3 of my builds to get it just right... main gear not touching frame (top and middle spacers), drive pulley in the right location (top spacer), and little/no up/down play of the main gear (middle and bottom spacers).

Usually takes me 2-3 tries to get it right.

If your drive pulley is very low, your lower bearing may not be seated in the bearing block. Check for up/down main shaft play in case is has seated, and you haven't noticed it yet. You may need to raise the shaft and re-position the mast collar.

[zguy]

Originally Posted by OverTemp

I think the main shaft bearings seat slightly differently in each frame set. They continue to seat for the first couple flights.

The spacer locations in the manual are good starting points, but I've had to adjust the locations and thicknesses on all 3 of my builds to get it just right... main gear not touching frame (top and middle spacers), drive pulley in the right location (top spacer), and little/no up/down play of the main gear (middle and bottom spacers).

Usually takes me 2-3 tries to get it right.

If your drive pulley is very low, your lower bearing may not be seated in the bearing block. Check for up/down main shaft play in case is has seated, and you haven't noticed it yet. You may need to raise the shaft and re-position the mast collar.

Thanks for the reply, but as I said in my post-
"I can remove the shims to bring the drive pulley upward, but it only makes the belt ride to the low side of the drive pulley and does not bring the belt off the lower lip of the guide pulley."

To put it another way, the drive pulley height does not seem to effect the belt position on the guide pulleys.

[taosgraveyard]

Yes, the lower lip of the left hand pulley was worn off, completely. I had thought u belt got loose and did this but noei think I had the same problem ar you

Thanks for this post, I will really look this over as I reassemble it.


Odd that this misallighment does not react to adjust,net



My 600se is fine.

Originally Posted by zguy

There is a geometry issue where the belt is riding on the lower lip of the LH guide pulley.

I've had two crashes caused by this failure and replaced both side frames and booms each time. Even if something was off/bent in the first, what caused the second with all new parts? BTW-the frames did not break in either crash, but rather were gouged out on the inside by the belt when it came off the guide pulley both times.

I'm now using the metal guide pulleys and the belt is still riding on the lower LH lip. I can remove the shims to bring the drive pulley upward, but it only makes the belt ride to the low side of the drive pulley and does not bring the belt off the lower lip of the guide pulley.

I have no idea why this appears to be effecting 500's vs. 600's

If anyone else has had issues, or even better a solution please chime in!

[taosgraveyard]

Originally Posted by OverTemp

I think the main shaft bearings seat slightly differently in each frame set. They continue to seat for the first couple flights.

The spacer locations in the manual are good starting points, but I've had to adjust the locations and thicknesses on all 3 of my builds to get it just right... main gear not touching frame (top and middle spacers), drive pulley in the right location (top spacer), and little/no up/down play of the main gear (middle and bottom spacers).

Usually takes me 2-3 tries to get it right.

If your drive pulley is very low, your lower bearing may not be seated in the bearing block. Check for up/down main shaft play in case is has seated, and you haven't noticed it yet. You may need to raise the shaft and re-position the mast collar.

Thanks i will look at this very carefully wheni reassemble


Good info

[weaser42]

I've had the same issue with my 500. When I first built it I shimmed by instructions and all was fine. Then after a rebuild I noticed my belt looked funny and on further inspection the bottom lip of a pulley was worn off and the belt had slid off and chewed up some of the frame. Replaced frame, pulley, and belt but same issue with belt riding too low. Looked at doing shims differently but if I move my main gear up it would be a pain to access the pinion set screw.

The 500 has just been sitting as I've been dealing with other issues and my Logo600 is flying great

I can't help but wonder if something somewhere has changed as my 500 was fine before the rebuild.

[taosgraveyard]

Exactly the same symptoms of wear as mine.

So you did not say' so I am asking...

Is there now, as it sits after you noted this wear, vertical play in the main shaft? I bet there is not, because you did a rebuild.

I am out of town now, but will check ,ine for vertical play when I return

When I crashed, all I knew is that I heard a screeching kind of sound and I lost tail control. As it came in hard, the sound stopped. I thought that the belt broke, and I must have had it too tight or too loose. I did not notice the worn pulley until I started the repairs. The left pulley shaft had almost come out of the lower slot, and the two spacers were badly worn and the lower lip was sworn off the pulley


I have some wear in the frame too, not too bad,

Originally Posted by weaser42

I've had the same issue with my 500. When I first built it I shimmed by instructions and all was fine. Then after a rebuild I noticed my belt looked funny and on further inspection the bottom lip of a pulley was worn off and the belt had slid off and chewed up some of the frame. Replaced frame, pulley, and belt but same issue with belt riding too low. Looked at doing shims differently but if I move my main gear up it would be a pain to access the pinion set screw.

The 500 has just been sitting as I've been dealing with other issues and my Logo600 is flying great

I can't help but wonder if something somewhere has changed as my 500 was fine before the rebuild.

[rifted]

I am having the exact same issue left side pulley and the belt keeps wearing off the bottom of the pulley.It started after replacing the frame. I have a 500 also, I wonder if there is a defect in some 500 frames. All the parts and spacers are the same as before I should not have to shim. The old frame had no problems and I used the factory spacers on the pulleys. You shouldn't have to add/change shims if you are using all original parts. I changed the frame after cracking it on a hard auto. I replaced the frame and now the belt keeps sliding off the bottom of the left pulley. I am going to recheck my tail geometry.

[Big Fil]

Out of curiosity, did you replace the boom after your crash?

[Real_Sparky]

I had a similar issue and replacing the boom stopped it.

Great question Phil

[Laughingstill]

The 500, 500se, 600, 600se use the same main shaft, bearings, frames so if you are having issues, you have not aligned the belt with the pulleys properly, you have vertical play in the main shaft, or the belt tension is not correct. Check those..........Ron