Can U Help Me Fix My Daughters Atv?

[williams]

Honda TRX70 made in the mid 80's. Problem is when shifting to 3rd gear ATV stops like tranny is binding. Once in third it will upshift to 4th and drive fine, but it will not downshift from 3rd to 2nd. Also when driving in 1st or 2nd there seems to be a ticking sound like something is getting tossed around in the tranny ocaisionally. Also it want pull a heavier person on a incline. Any ideas on where to start?? I am mechaniclly minded with automobile manual transmissions but have never taken on a bike tranny before. Is tearing into and taking apart the tranny something that should only be done by the experienced mechanics? If I can do this I also need pointers on where to start, like do I take both sides of the gear case apart or just one? Any tricks to taking this thing apart...... many thanks to whom so ever might take me under their wing on this one.

[mark40]

you may try to get a shop repair manual at a local bike shop CLYMER makes them sometimes you can get lucky and find them for older machines . i dont know if they will go into full detail of transmission rebuild . i bought an original shop manual from HONDA for my 02 400ex and it was very helpfull . good luck those older bikes run forever . :rider:

[David]

Try here http://www.repairmanuals.com/atvs/

Sorry we can't be of more assistance

[Snafoow]

Originally posted by williams@Apr 3 2005, 02:40 AM
Honda TRX70 made in the mid 80's. Problem is when shifting to 3rd gear ATV stops like tranny is binding. Once in third it will upshift to 4th and drive fine, but it will not downshift from 3rd to 2nd. Also when driving in 1st or 2nd there seems to be a ticking sound like something is getting tossed around in the tranny ocaisionally. Also it want pull a heavier person on a incline. Any ideas on where to start?? I am mechaniclly minded with automobile manual transmissions but have never taken on a bike tranny before. Is tearing into and taking apart the tranny something that should only be done by the experienced mechanics? If I can do this I also need pointers on where to start, like do I take both sides of the gear case apart or just one? Any tricks to taking this thing apart...... many thanks to whom so ever might take me under their wing on this one.
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You need to totally take the engine apart.
Remove the head and cylinder, both left and right side covers, remove the clutch and flywheel.

Make sure to remove all bolts for the center cases. When I split any center cases I like to lay the engine on its right side and carefully tap and pry the cases apart. I also tape on the countershaft and crank as I do this to help keep the shafts and gears in the right side case.

The trick to this is to keep all the parts in one case. Then you can look how it all goes and disassemble the trans and lay each piece out in order on the bench for reassembly.

Pay close attention to how the shift barrel and shift forks connect to each other and the order they where removed. A little tricky.

[williams]

Thanks. I think I fixed it, loose chain problem the whole time and adjusted clutch. Compression is a little low at around 100psi but it pulls her around fine. Will probably replace rings later, maybe valves.