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cr80 bottom end diagram manufacturer

- Oct 13, 2022 -

cr80 bottom end diagram manufacturer

Kits feature everything needed to complete crankshaft installation including Hot Rods main bearings and seals kit plus a complete lower engine gasket set that includes seals for a complete bottom end engine rebuild

cr80 bottom end diagram manufacturer

Crankshaft kits include crankshaft, top end bearing, premium main bearings and a complete bottom end gasket set that includes all seals and gaskets needed to do the job

Double-drilled small ends provide the piston pin with extra lubrication and cooling, reducing distortion of top end due to thermal transfer from the piston

cr80 bottom end diagram manufacturer

Next stop.....http://www.motosport.com/dirtbike/product/COMPLETE-TOP-BOTTOM-END-KIT/?prodId=287374&sMMY=HONDA;CR80;2002&src=usersearch&categorybox=&store_val=dirtbike

I didnt split the cases....once I found out my bike blew the bottom end I lost it, and decided to sell it as a roller. My bike was a complete lemon from the minute I brought it home, spent the money I sold it for and the money I would have spent on tools and parts and bought a 05 yz 125. Only because my bike was a total lemon and would have needed cases replaced also.

Like I said, you could pull the motor, mail it to Eric Gorr and get it back in perfect condition for WAY less then $1k. It makes no difference what the difference in labor cost is for Utah and Cali. I talked to Eric Gorr about my 2001 cr80 which is in need of a bottom end rebuild and I could have him stroke the crank (I was considering a 112cc upgrade) and still get it back for less then $1k. Don"t send it to a dealer and pay premium labor charges. Find someone reputable that will do it and you will save a bunch of money and get it back in just as good of condition as you would if you sent it to a dealer. (if not better. a lot of dealer mechanics are kids straight out of mechanics school.)

The mechanic I talked to said that he would charge 2 hours labor at aprox $85/hour. Spend another $100 on a newtop end and you have a brand new engine for less then $400. No reason to part out that 80, it is still a good bike that can be used for many years.

cr80 bottom end diagram manufacturer

Before removing the carb download the service manual for pictures, illustrations and diagrams for assistance with these procedures. Procedures differ between all years and models and the following should not be used as an exact guide.

Install the diaphragm/vacuum piston into the carburetor body by aligning the tab of the diaphragm with the air passage, then insert the jet needle into the needle jet. Lift the bottom of the piston with your finger to set the diaphragm rib into the groove in the carburetor body.

Connect the throttle cable to the throttle drum and install the cable adjuster into the carburetor body. Connect the choke cable by screwing the SE valve nut, being careful not to damage the SE valve. Install the carburetor into the insulator by aligning the lug with the groove, and tighten the band screw. Tighten the SE valve nut and connect the fuel tube.Now install the throttle drum cover by aligning its tab with the slit in the carburetor and secure it with the screw. Route the tubes and wire properly and connect the carburetor heater connector (See diagram in your service manual).

cr80 bottom end diagram manufacturer

In the early seventies, Honda had been one of the first Japanese manufacturers to take the mini class seriously with their original XR75. Refined, well-suspended and reasonably powerful, the little four-stroke had offered kids a great platform from which to start a racing career. Eventually, however, new two-stroke competitors from Suzuki and Yamaha eclipsed the modest performance limits of the XR. It was still a great play bike and competent beginner machine, but for hard-core racing, it no longer had what it took to run at the front.

Realizing they needed a boost in performance in the mini class, Honda unleashed an all-new model for 1980, the first CR80R Elsinore. Looking just like a three-fifths scale CR250R, the new mini featured a powerful 79.7cc reed-valve two-stroke motor, laid-down dual-shocks, and a stem-to-stern coat of fire-engine red paint. With its close-ratio six-speed gearbox, manual clutch and explosive power delivery, the CR80R was far more challenging to manage than the XR and aimed squarely at racers only.

While certainly more competitive than the underpowered XR, this new mini CR was not the game-changer the original Elsinore had been at its introduction. The motor was a rocket, but the chassis and suspension were far less successful. Both the forks and shocks were poorly damped, prone to bottoming, and harsh in action. When pushed, the shocks faded immediately and the bike bounced and deflected instead of tracking in the rough. With major suspension work, it was competitive, but in stock condition, it was less than ideal.

For 1983, Honda decided to pull out all the stops by once again completely redesigning their mini-class offering.As in ’82, the new machine continued to employ Honda’s Pro-Link rear suspension, but an increase in travel from 7.9-inches to 8.3-inches looked to smooth out the ride. Up front, the new CR continued to employ a set of 31mm Showa damper-rod forks, but new settings aimed to improve performance. On the motor side, the ’83 CR80R featured an all-new liquid-cooled power plant that Honda claimed pumped out just over 20 horsepower. It continued to employ a six-speed gearbox with a manual clutch and a maintenance-free solid-state CD ignition. On the chassis front, Honda spec’d an all-new semi-double-cradle steel frame to work with the new motor and revised Pro-Link. The new chassis lopped .4-inches off of the wheelbase for 1983 and steepened the geometry for improved turning.All the bodywork was new as well, with revised lines that mimicked the looks of David Bailey’s factory racer right down to the blue safety seat and more orange “Flash Red” colored plastic.

On the track, the new motor turned out to be a significant improvement in some areas and rather lackluster in others. Low-end response was better than ‘82 and the bike was snappy out of the hole for a mini class machine. The midrange was solid as well, but top-end power was completely lacking. On Kerker’s dyno, the Honda put out a peak of just over 14 horsepower, well below Big Red’s advertising claims and over two horsepower less than Kawasaki’s KX80 on the same equipment. With its strong low-to-mid delivery, the CR was liked by novices, but derided by faster kids who demanded more revs and a stronger pull on top. It was faster than the ’82 CR80R, but still not up to running with the class-leading KX in any test of speed. If you were an aspiring Mike Healey, you were likely going to need some major motor work in 1983.

On the suspension end of things, the ’83 CR once again skewed toward the novice side of the spectrum. It featured both the least travel in the class and some of the softest settings. Neither end offered any adjustments save spring preload in the rear. Compared to the class-leading KX, the CR gave up nearly two inches of suspension travel front and rear. While this made it a better fit for smaller kids, it significantly hindered its ability to take on larger whoops and the bigger jumps. Both ends were sprung extremely softly and underdamped for aggressive riding. With a larger or faster kid on board, the Honda would crash to the stops on any medium-sized hit. Even with a smaller rider aboard, both ends were harsh and underdamped.

Because of its overly soft suspension, the CRs handling could be a real handful in the rough. Under acceleration, the rear end squatted appreciably and rebounded suddenly when encountering the first bump or whoop. The soft forks did help the bike settle in slow turns and the CR was quite good in that department. Fast sweepers, however, were a white-knuckle affair as the bike bobbed and weaved on its overtaxed forks and shock. Keep the speeds down and it was a decent handler, but try to pick up the pace and it was brown-trousers time for junior.

Overall, the 1983 CR80R was an impressive-looking machine in need of some additional performance. If beauty won shootouts, it would have been unbeatable, but as it stood, it was too short, too heavy, and too slow to compete at the top. It was a good machine for shorter, younger, or inexperienced riders, but too limited for anyone above the novice class without some major upgrades.