Board index Flathead Power-Technical Questions, Answers, and Suggestions Big Twin Flatties repro rods

repro rods

Post Sun Nov 06, 2011 11:37 am

Posts: 162
Location: athens,greece
hello again,anyone here have any experience using the repro connecting rods that sell on ebay for 200$....
the ones with the oem cast numbers that are sold complete with crankpin etc......
any ideas on quality of the actual rods....other alternatives......
any info would be great...

Post Sun Nov 06, 2011 9:33 pm

Posts: 83
I bought this same v-twin set of UL replacement rods some time ago but didn't used it yet. Mine came without the oem cast code though. I didn't measure the pin bushings but when I tried a piston pin it looked a bit loose for my liking. Carrillo makes a 8" rod in their H-beam style and they have SOLID reputation, but pricey and not really a direct replacement, since stock is 7.902" length eye-to-eye. Piston will hit the head unless you dig a pop-up relief in the head; and maybe some work widening the recess for the rods on bottom of the cylinders, because the rod stem is wider than stock.

Post Mon Nov 07, 2011 1:11 am

Posts: 162
Location: athens,greece
THANKS HELSINGBORG.....a friend is currently running in a ul with these rods but he replaced pin ,rollers etc...keeping only
the rods in the end, everything as you say was way too loose.......he has done 4000miles so far the bike is running great....
i am getting ready to build a motor and am seeing what options i have ,thinking of doing the same.....

Post Tue Nov 08, 2011 5:59 am

Posts: 607
Location: Menomonie, Wisconsin, USA
I would rather rebuild a set of OEM rods for the same money. Just start with a good set. Jerry

Post Tue Nov 08, 2011 4:20 pm

Posts: 83
I tend to agree with Jerry...but remember, even a good set is a 70 years old grandpa :)

Post Mon Nov 14, 2011 5:15 pm

Posts: 219
Location: Georgia
The first complete rod/flywheel set I got from Teds Vtwin was completely installed before I realized they had the wrong rods installed. They were for an overhead valve engine and too short. I sent them back and got another set. I checked them much better before installing them. The second set rods were correct length but the rod side clearance measured about .100", and the wrist pin clearance was almost .005". I did use them but ended up treating them as if they were worn out.

Be very careful

Post Wed Nov 30, 2011 1:42 pm

Posts: 162
Location: athens,greece
thanks guys....did get a repro set in the end....will be redoing every thing,keeping just the actual rods........ as nothing oem came up,and using a jims crank pin instead of the one in the set........

Post Tue Jan 03, 2012 11:34 pm

Posts: 3
:roll: I would not buy the repro rods that Hawgcity sells on ebay!! I bought a set about 3 years ago, and thought they were the answer to what I needed. I finally got all the parts I needed to start on my engine (39' UL), but decided to not use the bearings that came with the rods. I looked at the crankpin, (a stepped pin), and thought I might want to have my flywheels machined and use the bigger taper, non stepped pin. I especially did not like the undercut machined in the pin where the taper ends and the bearing surface begins (it looked like a weak spot to me). Also when I threaded the nuts on the pin they were both crooked!!! The shaft was threaded ok, but the the threads on the nuts were machined crooked!! thankfully I had saved my old nuts an they threaded on ok.
I then measured the outside diameter of the crankpin (it should be 1.250") it measured 1.260" .010" oversize, not .001, but .010" oversized. I the measured the races on the big end of the rods an they measured 1.635" ( it should be 1.625").
the inside diameter is .010" oversize also!
In my opinion these rods are JUNK!!! There is no way I can use a standard crankpin, or a non stepped pin with these rods.I don't think anyone sells a .010" oversize crankpin!
The only thing I can do to make these right is to get a new crankpin and put the correct races in the rods.
But, the price of the races, crankpin, bearings, cages, and labor to replace the races end up being more than the rods initially cost.
Now I could take a chance and just go with this oversized stuff, but I just don't like the way this crankpin is machined.
I emailed Hawgcity through Ebay and explained everything to them, and asked if all the rod sets were like this, or was it just this one set.
They responded, "YES, THEY ARE ALL THE SAME. WE USE EITHER JIMS CRANK PIN OR EASTERN " (their exact words)
What I have is apparently Eastern, cause it has 3 oiling holes, but I wasn't sure I understood their answer. Did they mean the were all oversized, or that they were all supposed to be standard size? I don't know if there is such a thing as a .010" oversize crankpin.
So, I emailed them explaining again, and giving them the dimensions, again, and their reply was, "I'D GET A NEW CRANK PIN AND NUTS AND PUT IN NEW ROD RACES " (their exact words).
Apparently they don't give a rats ass about their customers!!
I responded that I figured that was what I had to do and that their rods were CRAP!!!
So, you can judge for your self if you want to go through all this trouble or not. As far as I am concerned these rods are scrap, cause scrapping them is what I would do with a set of old rod if the races were .010" oversize!!!!!!!

Update: Since I now do not believe a word those LIARS at Hawcity say, I decided to contact JIM'S MACH and EASTERN M/C PARTS and ask them about these oversize crankpins.( Hawgcity emailed me that they use either Jims or eastern crankpins.) Well Jims and Eastern told me they have never made any crankpins that were .010" oversize, which means Hawcity LIED, and these crankpins are probably some chinese JUNK!!!
Since I will probably upgrade my flywheels to the later non-stepped crankpin now, does anyone know of anyone who does this machining upgrade to the flywheels other than American Cycle Fab?
I wonder why S&S CYCLE,(you guys are famous for your connecting rods), does not make a set for harley UL/ULH?
I think we all would rather buy a set of S&S rods instead of this imported junk! They are making cylinders and heads. Maybe connecting rods, pistons, and flywheels in the near future? One can only hope!
Last edited by markcoc on Tue Jan 10, 2012 11:08 pm, edited 4 times in total.

Post Wed Jan 04, 2012 6:52 am

Posts: 426
Location: Tucson Arizona


That's a bad situation and I too would be upset. I'm not sure where Hawgcity gets their rods or why the crank pin was .010 oversized, but your comments about the Eastern crank pin made me go into the warehouse and measure the ones I stock. All the stepped pins (348-40) were spot on 1.250 and the 348-36 pins were 1.125

The rods I sell are from the same manufacturer as my 45 rods I've been selling for years with absolutely no issues. They're drop forged and of very good quality.


Post Thu Jan 05, 2012 2:33 pm

Posts: 83
My experience: I also bought the v-twin rod set some years ago and I think it's the same hawgcity is selling on ebay. When I measured the crankpin it was .010 oversize, same problem as your. I also have a Jim's UL pin single hole and the OD is the correct 1.25". My v-twin rods also have the undercut between the taper and the racer, but it's minimal and I don't think it's a big problem. Piston pin is very loose in the rod bushing, about same clearance fhsmith stated, or .005. Unlike yours, ckankpin nuts were fine. I didn't see a reason to replace the rod races (since you're using the same crankpin and cage/roller that came in the set) because the connecting rod lower end bearing clearance is fine.
BUT... I decided to buy Carrillo 8" rods, Jim's pin and cages. The v-twin rod set is now in some drawer somewhere in my garage. But I wrote down every problem I found, so if I decide to sell or trade the next owner will be aware of the issues. I think the set is usable since these issues are corrected, but machining work is money...right?
By the way, happy 2012 for you all.

Post Mon Jan 09, 2012 7:29 pm

Posts: 1676
Location: Interlaken, NY USA

Markcoc, Instead of machining your old flywheels to take the larger crankpin, you might just consider an alternate solution. I recently sold my stock flywheels on ebay, and for only about $50.00 additional, bought a set of T&O's torque monsters. Struck me as a win-win. Of course, I went with a little more stroke than stock, but you wouldn't have to ;-)

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