Sprag compatibility Buell! EBR

[Theycallmecrash]

I doubt anyone has had the need to investigate this. But I was curious if an EBR sprag is the same or interchangeable with the 1125 setup. Anyone have a source at EBR that knows maybe?

I can order EBR parts through my girls work, so if that was an option id go that route vs Harley.

 

[mrlogix]

the parts list for the 1190RX that has been released so far does not detail any of the engine internals. There is changes in the heads and cams from the 1125-1190RS-1190RX. Maybe halfagiraffe can call EBR and get a quote and part number to compare with the stock part number? They are updating the part numbers as the engineering changes supersedes the old helicon part designs. Make sure you post anything you find out please.

 

[Theycallmecrash]

Yup got her searching for me. Just figured id put this up see whats out there and ill post my findings in the end, pretty much just paranoid mines crapping out and gonna replace it as maintenance

 

[Cosworth]

Don't see why it wouldn't, but can't say for sure. I don't think that part of the engine architecture changed.

Its very similar to a Ducati spray as well

 

[Matteson]

And the ktm. I found a ktm sprag for 99 bucks once.

 

[mrlogix]

Matteson-KTM sprag does interchange?

 

[Matteson]

that I don't know. we would have to check on dimensions. but they look the exact same. i'll see if I can find it again.

 

[mrlogix]

the sprag clutch and housing are the same from the 1125 and the 1190RS. I bet they are the same for the RX/SX.

 

[bwylie_99]

Keep us posted. Sprags tend to go on these beasts!

 

[mrlogix]

anybody out there work with any sprag clutches?

found this doing some research

http://www.renold.com/Products/SpragClutchFreewheels/SO_SX.asp

requested some info on their website......

 

[mrlogix]

http://motorcyclecomponentshop.com/kw/starter-clutch-sprag

 

[mrlogix]

looking through forums and posts on motorcycle sprag clutch failures are due to lubrication issues. I'll have an 1125 engine apart here in a couple of weeks and will check into the oil gallery and sizing.

 

[Cosworth]

If you switch to a EBR oiling rotor which all 1125 owners should or they will be kicking themselves, then there is all kinds of oil being sprayed near the sprag, of course its on the opposite side but id assume its still getting some oil The 1125 crankshaft has oiling galleys and pressurized ports. My little bit of research showed the failures to be the retaining spring that engages the dogs in the sprag. Several ducati owners have noted replacing the spring can make the sprag work again.

Those little sprags are turning over quite a bit of compression on the 1125 at 12.3:1 compared to the XB at 10:1
On my bike if I try to start the bike on the compression stroke it struggles at times.

 

[mrlogix]

engine struggling to crank on the compression stroke would be a factor of starter motor and gear multiplication torque. Longevity of the sprag assembly seems to be lubrication related. Have read on different forums of European bikes and racing bikes that oil cleanliness related to sprag clutch spring binding up. So yeah, replacing the spring would help, but I want to fix it so as little intervention by me. That's how I got to be an engineer, just lazier than f*%k. lol.

 

[Matteson]

The longer I hear about this issue I have come to the conclusion that this part is a perishable item on this model like tires. They are expensive but that is the cost of high performance.
I have replaced many starting system gears and related components on many models. Two things I believe would have prolonged or avoided this
Never jump start the bike
And good oil

 

[Theycallmecrash]

So a sprag setup is more pr.less to reduce rotating mass right?

And yeah to me this seems like a wear item. 28k on my 1125 doubt its been changed. I just want to be prepared, im tired of my bikes being down months at a time.

 

[mrlogix]

mines out. Getting ready to order parts from surdykeHD.

 

[Cosworth]

surely they have made revisions to the sprag on the 1190 bikes to improve durability, depending on the price and when parts become available I think it'd be worth looking at one to replace the 1125 oem sprag.

There is quite a few manufacturers that use starter sprags like ours, ducati, aprillia, bmw, yamaha. They all seem to cite part failures. Although it seems to be higher millage maybe around 25-28k or more, which I do agree shouldn't be a considered a consumable.

One other thing Ive noticed is if you look at our sprag we generally consider the entire part that bolts to the rotor as one part when thats not true, its actually a sprag housing and sprag bearing held in with a keeper/c-clip. It seems to be that once the sprag weakens it starts chewing at the housing which causes that metallic paste those with failures have noted. Once that happens you have to replace the entire assembly.

 

[mrlogix]

crash- the sprag is a reduction in mass, but is a different smaller footprint for a bendix on a traditional starter like on cars

cos- the fine paste found at failure seems to be the sprag material its self. It is the wear item. The sprag housing get destroyed in the process. The principle of the sprags lightly freewheeling per se during engine run is highly dependent of a continuous light film of oil because the spring keeps the sprags in constant contact with the inner and outer race surfaces. It would be considered a consumable because each startup is technically dry with over-speed from the engine starting happening for a second or sub second duration before oil is filled in the oil galleries.

 

[Theycallmecrash]

Official word from EBR. Not compatible

Doesnt mean ive given up. Itll be a bit here, but ill tear mine down, pull and start the search for a direct source.
Also if anyone could find out a replacement TPS as they can only be purchased as a whole throttle body now