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Connecting Rods and Bearings

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Here's some connecting rod, and bearing info I'm collecting. I was hoping the photos would show up. I guess I'm still a dumb ass at this

Left to right are Stock OEM - Hot Rods - Carrillo

You can see the quality the Hot Rods and Carrillo show over OEM.

The Carrillo is a thing of beauty and almost the same wieght as the much smaller and weaker "looking" OEM. Much like comparing a CP piston to OEM.

Weight is as follows:

OEM - 246 grams

Hot Rods - 278 grams

Carrillo - 252 grams

The bearing cage photo's are showing wear at just over 34 hours.

You can see the rollers are wearing into the sides of the cage. And there's more wear on the thrust washer than I'd care to see.

http://s1291.beta.ph...C00701.jpg.html

http://s1291.beta.ph...C00700.jpg.html

http://s1291.beta.ph...C00699.jpg.html

http://s1291.beta.ph...C00698.jpg.html

http://s1291.beta.ph...C00697.jpg.html

http://s1291.beta.ph...html?sort=3&o=1

http://s1291.beta.ph...html?sort=3&o=0

Edited by nesc103y

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nice work. It looks like the hot rod and carillo rod have inserts in small end whereas the oem just has a plated small end. Is that right?

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nice work. It looks like the hot rod and carillo rod have inserts in small end whereas the oem just has a plated small end. Is that right?

Yes that is correct. OEM has no insert or plating. Just the machined surface. The HR and Carrillo have brass inserts.

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Interesting pictures, thanks for posting. I thought KTM was the only manufacturer with no bearing on the small end. That Carillo looks sweet.

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as far as I know, none of the four strokes have bearings on the small end. At least the ones I have worked on anyway.

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I rebuilt a CRF250 crank for a customer that was built with a Carrillo long rod this past season. What I found was after close to 40 hours of abuse there was minimal bearing cage, and thrust washer, wear. It looked like the setup could have easily gone another 20 - 30 hours.

So this has me wondering if the cage and thrust washer wear is due to side load created by an inferior OEM rod, or some other load the Carrillo doesn't inflict.

KTM 250's use the same lower bearing as the Honda. And bearing life doesn't seem to be as big an issue with those bikes as the Honda.

Or its possible due to the lower numbers of KTM's around you just don't hear of it as much. Its also interesting that KTM doesn't use side thrust washers.

I have a bunch of used rod/bearing assemblies from Honda 250's and 450's and in both cases I find one thrust washer with severe wear and one with minimal wear.

I'm building some 450 cranks with Carrillo rods now. So I'm hoping to collect more useful info.

Edited by nesc103y

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as i have said in the past its the cage that fails along with the thrust washers the washers can fail from not enough lubrication i went through this on harley engines we were racing restricting the oil feed hole caused them to go away quicker i have been using a #51 drill in the end of the cranks to get more oil to the cages and washers but im alsp doing other mods to get the oil out of the crank case.

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It could be crank flex on the left side?

curious question: when i pull my motors apart the cranks seem to always be between .010-.015 tir on the flywheel side and always high on the rod pin side. it takes about 3 good whacks with a brass hammer to get it back to .0005. What is the point in truing if it just moves back? I would think any sudden stop or reverse torque on the motor could knock it out. The crank i just pulled was spinning 11,700 with this: nice carrillo copycat.

IMG_2748.jpg

IMG_2739.jpg

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I think for most riders oem or hotrod is the most practical, unless carrillo has come down. Last time I checked it was like $600? I'm in need of a crank service as we speak, so I'm all ears.

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I think for most riders oem or hotrod is the most practical, unless carrillo has come down. Last time I checked it was like $600? I'm in need of a crank service as we speak, so I'm all ears.

There 275$$$ for carillo u can get a moose racing one which is made by carillio with there name on it for 249$.... RON have u played with cryogenically hardening cages rollers or washers?? I know formula 1 indy and trophy truck teams cryo nearly every part in the motor with great results. Alot of road race street bike high hp bikes also use same thing to greatly increase part life

Edited by Dasquriel

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It could be crank flex on the left side?

curious question: when i pull my motors apart the cranks seem to always be between .010-.015 tir on the flywheel side and always high on the rod pin side. it takes about 3 good whacks with a brass hammer to get it back to .0005. What is the point in truing if it just moves back? I would think any sudden stop or reverse torque on the motor could knock it out. The crank i just pulled was spinning 11,700 with this: nice carrillo copycat.

IMG_2748.jpg

IMG_2739.jpg

weld.

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Now that i have got very close access to cryro im going to use it more i have used it in the past with good result i have also tested coating the cages in the past thers a company in detroit Hi tech coating tthey have a coating that stays on pistons and burnishes in ford was using them for there supe chargers on the rotors it increased the effincency a bunch i have had pistons coated with it also .

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Now that i have got very close access to cryro im going to use it more i have used it in the past with good result i have also tested coating the cages in the past thers a company in detroit Hi tech coating tthey have a coating that stays on pistons and burnishes in ford was using them for there supe chargers on the rotors it increased the effincency a bunch i have had pistons coated with it also .

http://www.twostrokeshop.com/peek_coated_big_end_bearing.htm ron have you ever used this? Or heard of it?

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no i had never used it or heard of it but it makes good sense i beleive the coating from hi tech would be a better solution for the same problem.

Whats the coating called? Theres a few comanys called by that name in that area?

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Whats the coating called? Theres a few comanys called by that name in that area?

Line 2line coating

clarkston michigan

248-625-3052

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as i have said in the past its the cage that fails along with the thrust washers the washers can fail from not enough lubrication i went through this on harley engines we were racing restricting the oil feed hole caused them to go away quicker i have been using a #51 drill in the end of the cranks to get more oil to the cages and washers but im alsp doing other mods to get the oil out of the crank case.

If you're drilling the feed hole how are you cleaning the shavings out. Or are you drilling it when the crank is apart?

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If you're drilling the feed hole how are you cleaning the shavings out. Or are you drilling it when the crank is apart?

What size are you boring them out too?

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they have to be apart to do machine work. besides new needs worked on, so buy a new crank and do it up or redo what you have.

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