Technical Review: AB2101, High Lift Blade on 20" mower (modification)

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  • Updated 2 years ago
  • (Edited)
*** DISCLAIMER ***
The AB2101 is for the 21" mower; Ego does not endorse modifying equipment!

Summary:
The 21" AB2101 high lift (HL) blade can be modified to fit the 20" LM2000 mower.  Wet weather precluded a relevant test of the bagging performance.

Background:
The AB2101 HL blade is highly anticipated for its purported ability to increase bagging performance on the 21" mower.  The 20" mower with the standard blade does not seem to have the same issue.  The AB2001 is the HL blade for the 20" LM2000 mower, but is NOT available in the US.

Differences (21" HL vs. standard 20"):
The HL blade has large wings at the tips to generate additional air flow. Another member posted pics, and the dimensions of the wings are approximately: 3" in length, 1" additional width, and 1" lift.

Image: two stock 20" blade, with the modified (cut) HL blade in the middle.


Modification (to fit 20" mower):
A) The mounting system between the 20" and 21" blades are different.  The 20" has a round hole and a slightly larger 3/4 hole (keyed). The 21" has the same round hole on both sides.  The 21" blade will NOT fit directly on the 20" mower.  I will not be covering the details on the modification required (other than what is shown in the pics).
B) The blade is 1" longer (duh!), so I had to remove 1/2" from both ends.  I maintained the same contour as the part that was cut off.
C) Balance was verified post "chop".





Installation Notes:
The mower chassis (skirt) had previous strike marks (probably when I hit the big rock that dislodged the magnet), so I colored it yellow so that I could see any new contact between the blade and chassis.
Blade comes within 1/2" of the skirt at the 3 and 9 o'clock positions (sides), and is further away at the 12 and 6 o'clock positions (approximately 1").



Videos:
I wanted to see if the mower sounded different with the new blade, and whether you could hear a difference between height setting #6 (high) and #1 (low).  I couldn't really hear or tell a difference between the two.  But the significant other said the sound was deeper and more muffled; however, that could have been completed related to mowing WET grass.  First video is #6 (high), and second is #1 (low).




Vacuum Performance:
One thing that I was able to test was to vacuum up (and mulch) some leave that were under my small Puakenikeni (flower) tree; the dried leaves pictured are 6-8" in length.  I also have Ti Leaf plants, and those dried leaves are about 4" wide by 12-16" long, and the mower will pick-up and mulch those all day long, even with the standard blade.  Additionally, when I ran over areas with little grass (dirt), the mower did seem to "vacuum" up more dirt than I recall before (and everywhere was WET).  Conclusion: Vacuum performance appears to have increased, but further tests are required.




Mulching Performance:
So I just cut the grass to height #1 two days ago (see thread link at end); and it has been raining both days since, so I didn't want to fill my catch bag with soggy wet grass.  So the test I did was mulching.  When I cut last, I will run back and fourth until it won't cut anymore.  So today with the HL blade, it was still able to cut more grass; which could either be because it grew "that much" in two days, or that it might be pulling the grass up to cut it more.  Conclusion: non-ideal test conditions (WET), but the mower still mulched as well as the standard blade.








Battery Temps:
The other day it was 85F middle of the day and bright sun.  This evening (17:30) it was drizzling and over cast, ambient was 80F.  The temp under battery cover was 85F, which is 50F different than the other day; so another indicator that the mower was not doing much work as there wasn't much grass to cut.  Battery internal vent temp was 92F vs. 104F, a 12F delta.  Conclusion: Overall temps were lower due to both ambient temp (5F delta), as well as low load on the mower.




Follow-On Tests:
1) Bagging of DRY grass
2) Mulching of taller grass (e.g. not cut 2 days ago)
3) Static test of vacuum performance (garbage bag over catch bag, time how long it takes in inflate)
4) Vacuum up cut grass from side walk at various mower heights (standard blade at setting #1 [low] works okay for me)

Conclusion:
The 21" blade was successfully adapted to the 20" mower, the mulching/vacuum performance seem to be as good if not better than the standard blade.  And follow-on test are required to evaluate the  bagging performance.

Related Threads:
My last 20" mower review
https://community.egopowerplus.com/ego/topics/learning-to-l-e-a-r-n-or-teaching-an-old-dog-new-trick...

20" mower field repair:
https://community.egopowerplus.com/ego/topics/20-mower-field-repair-of-the-motor

My first 20" mower review
https://community.egopowerplus.com/ego/topics/20-mower-once-the-warranty-is-no-longer-valid
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(a)Typical Engineer

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Posted 2 years ago

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Blue Angel, Champion

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Nice write up.

I believe your conclusion should be, further testing required to evaluate both mulching and bagging performance. The test you did certainly didn't seem like a normal test of mulching ability since you had just cut two days earlier? Mulching ability is usually graded on the ability to re-cut the clippings shorter before they fall to the lawn.

The wet part certainly throws things for a loop also.

What tool did you use for rounding out the 3/4 hole?
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(a)Typical Engineer

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Agreed, that further testing of the mulching is required, and initial testing was very promising.

The blade (as has been extensively discussed) is very soft steel, so standard drill bits and files to modify the mounting holes. That's a benefit of the non-hardened steel, "ease of manufacturing" which goes towards the "producibility" of the item. They coils have made us harder but the price might have went up to $30. I would gladly pay that, but the next guy might say that's too much. Life is (sometimes) about adapting to the situation before you.
(Edited)
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Blue Angel, Champion

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I learned the "hard" way, HSS drill bits are no match for ordinarily hard mower blades. So punny...
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Steve Valdes

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That's the most thorough, impressive review that I have ever seen. Nice work!
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Steve Valdes

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Pictures. videos, modifications and more.
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(a)Typical Engineer

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Follow-On Tests:
5) Use sound meter to compare the difference between the standard and HL blade.
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(a)Typical Engineer

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Summary: Blade noise comparison between the STANDARD and HIGH-LIFT blades

Test Setup: All test were conducted in the drive way (not in yard) to minimize surface difference variables

Measurement Equipment: iPhone decibel app, measured 2 fee above center of mower

Test Configuration & Results:
A) height #1 (low) vs. #6 (high); within 1 dBA of each other, so negligible (higher=louder).
B) Mulch Plug vs. Bag: about 3 dBA difference, bagging is louder (expected).
C) STD vs. HL blade: within 1 dBA of each other, so negligible (maybe the tone is different).

Observations: If you compare the two videos, within 1 second of start-up, the HL blade inflates the bag noticeably quicker than the STD blade.

Data: All test results were in the 88 to 92 dBA range (not enough difference (for me) to post all the screen shots.

Conclusion: Blade noise between the STANDARD and HIGH-LIFT blades is similar, regardless of height of cut.  Bagging is louder than mulching by 3 dBA.


Pictures:


Videos:
STANDARD blade


HIGH-LIFT blade
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shedman

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The two videos are quite good.  The HL video clearly shows a bag that is "full", whereas the SL video the bag (up near the edge of the cover) is "waffling", ie: the pressure is not high enough to keep it full.  Thank you for posting these.
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Pongajim

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Wonderful story but not true for everyone. The high lift blade is a bit better than the standard but not nearly sufficient to pick up grass and debris especially when the mower slows down for lack of torque demand. A much better solution is to get an aftermarket high lift blade from the big box stores. It includes an adapter kit to fit most every mower on the planet. The higher the lift the more airflow and the more noise. EGO is just trying to keep the db down and increase the lift at the same time but it doesn't really meet many customer needs. If you really want lift, get the aftermarket kit.
(Edited)
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szwoopp, Champion

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Nice comment but equally not true for everyone.  I find the HL blade to work very well for bagging providing a lot of lift of leaves and debris.  Results seem to vary greatly based on lawn type, cutting height nad user expectations.

Also, I thinkthe use of a generic blade may void your warranty.
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(a)Typical Engineer

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+1 that an after market blade will VOID your warranty, as well possibly having too much load for the mower.