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Stevel
Posted on Wednesday, May 03, 2017 - 03:59 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

There is a fellow selling on eBay a parted out RX at truly ridiculous prices, but in doing so, he has taken very good photos of the individual parts. I have asked repeatedly on this forum and at EBR if there were any casting changes made to the original 1125 castings to facilitate the bore increase from 103mm to 106mm and never received the answer. Well, we now have the answer. Check this eBay link http://www.ebay.com/itm/282455761378?ul_noapp=true
It is clear that the much thinner wall in the photo says the answer is no.
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Panshovevo
Posted on Wednesday, May 03, 2017 - 09:49 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Considering that there is a $250 core charge (IIRC) on the cylinders when you buy an 1190 big bore kit for an 1125, I would have said it was a pretty safe bet.

Not a guarantee, but a pretty good bet.
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Stevel
Posted on Thursday, May 04, 2017 - 04:50 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

The cost of new casting molds is very expensive and I believe was the main influence in the decision not to build new ones for both the cylinders and the heads.

I believe the original decision to build the Helicon to 1125cc was due to marketing influences at HD, not common sense. I do not assess blame to Erik for this. It most likely was a necessary compromise. The proof of this was the immediate effort to increase the displacement by Erik once the freedom was in hand to do it. I am relatively certain the faults in both the heads and cylinder designs were recognized very early on, but because of costs, were never corrected. These design faults started to become visible to the public during the disastrous WSB effort, but was never admitted by EBR. I have identified these faults several times in previous posts on the forum, so I won't repeat them again. Unfortunately, living in Germany, I never had the opportunity to examine an 1190 motor physically, so I could never state my suspicions as fact.
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Panshovevo
Posted on Thursday, May 04, 2017 - 04:18 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I believe I read somewhere that in order to get Harley to go along with the Helicon motor, Erik had to agree to make it smaller than the original V-Rod motor (1130cc, I believe)

Stevel, I'm not sure I've read all of what you've written about the faults of the heads and cylinders.

Would you do me the favor of sending them in a message, if you don't feel like posting them again?
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Duanelr
Posted on Monday, May 08, 2017 - 01:15 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Ok, I'll bite. Briefly, what design fault do you see in cylinder?
(Gawd, out of all the problems with this bike, cylinder and cylinder-head have never seemed to have been an issue)
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Stevel
Posted on Tuesday, May 09, 2017 - 05:04 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I didn't think I would have to do this again. I thought you could search the web site by author, but It didn't work for me, so I assume others are having the same issue.

Essentially, the cylinder is weak and unstable dimensionally. Casual examination reveals that the cylinder has a wall thickness of 8.2mm at the thickest point and 5.1mm at it thinnest (1125). Turning the cylinder casting upside down, you will note that the bore is supported by 4 equidistant areas allowing 4 water passages into the open water jacket. These lower attachment points extend upward about an inch leaving 36mm to the deck top, but at the top there is only one attachment point at the chain case. This is an open deck design and from a thermally and torsional basis, weak and unbalanced. Add to this the casting material being aluminum. Aluminum has a much greater coefficient of expansion (COE) than say iron. Note that this imbalance and weakness occurs at the top of the cylinder where the temperature stress and pressure loading is at its greatest. Now lastly consider the mounting point to the frame is at the front cylinder head where all the cornering chassis stress is transmitted to the engine. Consider also that the engine is an integral functioning component of the chassis design. Then take 3mm away by boring it out to 106mm and you end up with a cylinder that is unable to remain round or in place under load. These observations are not just common sense, but I have personally seen signs of valve to piston interference marks on the edge of the valve reliefs on the pistons, where statically there was more that .5mm of clearance with a clay check. Of course we don't subject our bikes to the same loading on the street that the bike experiences on a race track, nor do we run racing fuel with more than 15 to 1 compression ratios either, but this is what was done during EBR's WSB effort. We also witnessed multiple head gasket failures as well as total engine failures. At the time there was excessive finger pointing and excuses like head bolts/studs and poor assembly, but my money is on the cylinder design.
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Ceejay
Posted on Thursday, May 11, 2017 - 10:18 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

There aren't any mounting points on the front cylinder - that was the XB and tuber engines. That's not to say the rest of what you state is incorrect (I woudn't know), just letting you know that watercooled motors have one mount between the cylinders and another over top the transmission - very similar to ducati mount postions.
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