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I've noticed on my three month old HRX217HYA mower that the throttle lever can be pushed beyond the "FAST" indent to the end of the slot. Doing this increases the the engine RPM and of course, the blade speed. I've been doing this while mowing to achieve a better cut but, I'm not sure if I may be over revving the engine.

Is this supposed to happen? Does this mean the engine is not running at the correct rpm when in "FAST" position? Do I need to adjust the cable length and/or carburetor so the "FAST" indent position runs at the same max RPM as at the end of the slot, or should I just run it at the "FAST" indent and leave well enough alone? I've ordered the shop manual and a "Digital Hour Meter Tachometer" so if needed I can make adjustments.

I would specially like to hear from Robert to see what Honda's position is on this.

Re: Honda HRX217HYA - Pushing throttle lever further than "FAST' Indent position?

When the throttle is in the FAST detent, a properly tuned engine should be turning at 3,100 -0/+150 rpm. This ensures the mower's blade tip speed is safe/legal, per the US Consumer Product Safety Commission rules.

You're smart to use a tach to check it, and the adjustment procedure is pretty simple.

I'll try and get with our service engineer for mowers and ask if/why the throttle can be moved beyond the FAST detent.

Re: Honda HRX217HYA - Pushing throttle lever further than "FAST' Indent position?

My HRX217HYA did this as well. I adjusted the throttle cable so the lever would stop at 'fast' and in the process gained a few revs, maybe 100-200 (I don't have a tach).

Re: Honda HRX217HYA - Pushing throttle lever further than "FAST' Indent position?

robert@honda said:

When the throttle is in the FAST detent, a properly tuned engine should be turning at 3,100 -0/+150 rpm. This ensures the mower's blade tip speed is safe/legal, per the US Consumer Product Safety Commission rules.

You're smart to use a tach to check it, and the adjustment procedure is pretty simple.

I'll try and get with our service engineer for mowers and ask if/why the throttle can be moved beyond the FAST detent.

Click to expand...

Thanks for the reply Robert. I look forward to the service engineer's comments.

Re: Honda HRX217HYA - Pushing throttle lever further than "FAST' Indent position?

TLAR640 said:

My HRX217HYA did this as well. I adjusted the throttle cable so the lever would stop at 'fast' and in the process gained a few revs, maybe 100-200 (I don't have a tach).

Click to expand...

Ultimately this may be the solution. Let's see what comments Robert brings back from the service engineer.

Re: Honda HRX217HYA - Pushing throttle lever further than "FAST' Indent position?

robert@honda said:

When the throttle is in the FAST detent, a properly tuned engine should be turning at 3,100 -0/+150 rpm. This ensures the mower's blade tip speed is safe/legal, per the US Consumer Product Safety Commission rules.

You're smart to use a tach to check it, and the adjustment procedure is pretty simple.

I'll try and get with our service engineer for mowers and ask if/why the throttle can be moved beyond the FAST detent.

Click to expand...

Robert, any luck in checking with your service engineer about this issue?

Re: Honda HRX217HYA - Pushing throttle lever further than "FAST' Indent position?

So the black throttle lever on earlier HRX models with a manual choke had a detent position for FAST and then another past that for CHOKE. When Honda updated the engine with AutoChoke, the throttle lever did not change, thus if you force the lever past FAST, it will still move into a more forward position. Under some instances, this might bump the throttle slightly and engine speed could change.

So, just don't force the lever past FAST. A properly tuned engine will provide correct, maximum speed when the lever is kept in the FAST position. At some point, Honda will change the throttle lever design, and that's when the unused detent will probably be phased out.

Re: Honda HRX217HYA - Pushing throttle lever further than "FAST' Indent position?

If the governor is set proper I don't see how you can over rev the engine, I would assume this would be set from the factory. Also I would assume very few people would own a hand held tachometer to check their RPM's unless they own a repair shop. Is this a common problem for Honda?

Re: Honda HRX217HYA - Pushing throttle lever further than "FAST' Indent position?

reynoldston said:

Is this a common problem for Honda?

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No. Honda checks/adjusts the engine speed on every single mower at the factory. As a result, there are very few warranty claims or dealer field reports for improper throttle setting.

Re: Honda HRX217HYA - Pushing throttle lever further than "FAST' Indent position?

robert@honda said:

So the black throttle lever on earlier HRX models with a manual choke had a detent position for FAST and then another past that for CHOKE. When Honda updated the engine with AutoChoke, the throttle lever did not change, thus if you force the lever past FAST, it will still move into a more forward position. Under some instances, this might bump the throttle slightly and engine speed could change.

So, just don't force the lever past FAST. A properly tuned engine will provide correct, maximum speed when the lever is kept in the FAST position. At some point, Honda will change the throttle lever design, and that's when the unused detent will probably be phased out.

Click to expand...

Thanks Robert. That makes sense. I'm surprised Honda didn't update the throttle lever at the time. It doesn't seem to be an big mod. In any case, I checked the rpm with the tach and indeed it goes up when pushed past the detent. However, I also noticed the rpm is a bit low at 'fast' detent (about 2900 - 2950). So, I think I'll adjust it by following the shop manual procedure. If I recall correctly, you do this by adjusting the throttle cable and linkage on page 3-14 and if necessary, bend the 'governor spring arm' to the left to increase the speed. The bending of the arm is the part I don't like!

Re: Honda HRX217HYA - Pushing throttle lever further than "FAST' Indent position?

Nitrohawk said:

The bending of the arm is the part I don't like!

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While it is not an elegant method, it is rarely needed but is effective. Some Honda dealer techs tell me it is "better" than previous spring-loaded, set-screw-type designs, as it won't change as easily (no screws to come loose), and deters a casual customer from fiddling with the settings. I know the emissions rule groups have some regulations that require engine manufacturers to discourage what is seen as "tampering" with parts of the engine that change the emissions profile, and max speed (and idle) adjustments are probably in that group.

Re: Honda HRX217HYA - Pushing throttle lever further than "FAST' Indent position?

robert@honda said:

While it is not an elegant method, it is rarely needed but is effective. Some Honda dealer techs tell me it is "better" than previous spring-loaded, set-screw-type designs, as it won't change as easily (no screws to come loose), and deters a casual customer from fiddling with the settings. I know the emissions rule groups have some regulations that require engine manufacturers to discourage what is seen as "tampering" with parts of the engine that change the emissions profile, and max speed (and idle) adjustments are probably in that group.

Click to expand...

The tach showed the rpm at 'fast' indent to be 2940-3060. So, I followed the shop manual instructions (p. 2-22, or p. 3-14) to adjust the throttle cable and linkage which to summarize says:

1. Move throttle to 'fast"
2. Loosen cable locking clamp and move cable backward until control lever A stops moving but no more.
3. tighten the cable locking clamp.
4. Start the engine, warm up, engage Roto-Stop, and measure the rpm.

Well, after doing this rpm improved slightly but not enough. But worse, the engine would not stop when moving the throttle lever to 'stop'! I repeated the above steps EXACTLY, twice more. Same results, could not stop the engine! So, I reversed all the steps back to the original positions and of course the engine stops fine now but the rpm is still below specs (about 3000).

So, the next step according to shop manual, and as Robert also mentioned is to bend the governor spring arm ever so slightly to get the correct rpm. I haven't bent it yet but I played with it a bit by hand and sure enough it changes the rpm! Now I just have to bite the bullet and bend it for good and leave all of the above adjustments as it was originally. Only problem is, the bend on the spring arm tab is NOT on the thickness side of the tab but rather on the wide side (I hope this makes sense!). Very awkward indeed! I hope I'm doing this correctly.

Here is the tab I'm I'm talking about:

Re: Honda HRX217HYA - Pushing throttle lever further than "FAST' Indent position?

have a real close look.
behind the throttle plate is a small microswitch.
This is the ignition switch so if you move the outer so far back that the throttle lever does not make contact with the ignition switch, it will not stop.
On some mowers there is some adjustment in the switch and some throttle levers have a tab that pushes the ignition switch which could be bent a little to vary the on : off positions.

Briggs have been using the "bend the lever" method of adjustment for over 60 years so it is not new.
About 2/3 of the "my mower dosn't run properly any more " repairs are simply bending the lever back to original position after the owner has pushed it into some bushes and a branch bends the throttle lever backwards.

At least Honda put theirs where it can not be bent during normal mowing.
Victa realised this was a problem back in 1960 so designed a carburettor that couls not be damaged in normal use and ran the throttle cable down the snorkel so it could not get caught on bushes.
Honda will eventually catch up ( they have finally started to fit snorkels ) but I doubt Briggs ever will.

Re: Honda HRX217HYA - Pushing throttle lever further than "FAST' Indent position?

bertsmobile1 said:

have a real close look.
behind the throttle plate is a small microswitch.
This is the ignition switch so if you move the outer so far back that the throttle lever does not make contact with the ignition switch, it will not stop.
On some mowers there is some adjustment in the switch and some throttle levers have a tab that pushes the ignition switch which could be bent a little to vary the on : off positions.

Briggs have been using the "bend the lever" method of adjustment for over 60 years so it is not new.
About 2/3 of the "my mower dosn't run properly any more " repairs are simply bending the lever back to original position after the owner has pushed it into some bushes and a branch bends the throttle lever backwards.

At least Honda put theirs where it can not be bent during normal mowing.
Victa realised this was a problem back in 1960 so designed a carburettor that couls not be damaged in normal use and ran the throttle cable down the snorkel so it could not get caught on bushes.
Honda will eventually catch up ( they have finally started to fit snorkels ) but I doubt Briggs ever will.

Click to expand...

Sounds like I have to take a closer look to find the micro ignition switch. Also sounds like it may be difficult to locate/see. So, if I understand correctly, I should make the cable linkage adjustment to make sure it still makes contact with the micro switch.

Still, I hate having to to bend the governor spring arm/tab the way it is oriented!