Heads Up on New HS 4 Stroke Clutches

I bought my new clutch from them recently and it's definitely better than what my 4G came with. My bike runs better than ever, kudos to B-E!

As far as engagement goes, these HS49s will lug under ~3800 RPM, and a higher engagement will be harder on the drivetrain. I find the new clutch perfect, myself.

Solution for you maybe, push-off from a start, pedal once or twice, then pull that throttle!

At what speed is it engaging now compared to the old clutch? Also, what speed does it disengage for coasting? I found that with a wet clutch that you can vary things a lot just by what fluids you use and how much in different combinations, which for me adds a lot of flavor to things. Maybe that will be a popular topic someday, but there is no need to go on about that.

My July 2010 4G came with a clutch that was too large for the shaft and engaged <2000RPM. It was hard for me to keep the clutch shimmed straight, so it sometimes locked the drum, which would of course stall the engine at idle. OCscully gave me some 58lb springs for the clutch (he found 60 to be the best on our old-style clutches, stock was ~40) and that helped out a lot, but still engaged at idle when hot. However, my clutch was still oversize and would sometimes get cockeyed on the shaft. The HS has a goofy metric keyway and you pretty much need to hand file a .187 to fit, and do it right. I pretty much lived with it and it kinda unstuck itself after a few stop-and-gos. Made new keys as needed because that crap banged around.

Through January 2012 after passing the 4000 mile mark, the clutch locked really bad and my setup could not idle at a stop for weeks. One night the T-belt rotor detached from the clutch drum, like it did back in 10/2010. I had it welded back then, but over time the keys and the sloppy clutch had eaten up the whole weld! Also, the clutch shoes were not worn out, but the inner hole had wallowed out bigtime. Was starting to get some clutch grinding on the engine. Timely break.

I ordered a new clutch and drum, and what's offered now is definitely better than what my 4G came with. The new drum and rotor are put together like shown in cobrafreak's post, whereas the old was simply pressed in and maybe half-soldered. My new clutch engages smoothly towards lockup (~3K) with my light pedaling and allows easy idling, just slightly starts to engage when very hot at a stop, prolly due to the bushing crap I need to get rid of. My engine idles 1900-2100.

I would've thought the freewheel feature would've make life a lot easier on those keys. Guess not.

Well if the clutch fits on the shaft properly, the key will last a lot longer. It won't get banged up.

The_Aleman said:

Well if the clutch fits on the shaft properly, the key will last a lot longer. It won't get banged up.

Click to expand...

Yeah, it's hard to find good help nowadays. You'd think that you would get a little more precision from an .87 cents an hour machinist.

The_Aleman said:

I bought my new clutch from them recently and it's definitely better than what my 4G came with. My bike runs better than ever, kudos to B-E!

As far as engagement goes, these HS49s will lug under ~3800 RPM, and a higher engagement will be harder on the drivetrain. I find the new clutch perfect, myself.

Solution for you maybe, push-off from a start, pedal once or twice, then pull that throttle!

Click to expand...

Do you happen to know what MM OD that clutch is? And does it fit the shaft without too much play? I don't know if they all the same or not, but the shaft on my 142f is slightly less than 15mm.

I got a reply from www.bicycle-engines.com/‎
about this.

"Our 5/8 Clutch O.D.= 82mm or 3.22835 inches

Our Clutch bell O.D.= 88mm or 3.46457 inches

Our Clutch bell I.D.= 84mm or 3.30709 inches "

For the few Hoot guys out there, this means we are in the money, honey! You may have to shim your shaft though because the older HS142F shaft for these gear boxes was slightly smaller than the newer motors that accept these clutches. I had to order a new motor anyways. Will update if any problems.

I've seen another member here use plumber's putty to lock it down. He told me "leave the clutch base on the shaft, service/replace the shoes as necessary".

Been following that method since and have to agree 100%.

So are you saying the new 142f's with the attached "hoot" gearbox come with this new clutch? Or would you need to order it as a replacement?