[PeppyDan]

Hello to all and thank you for being here to help us newbies to the atv world. I recently traded a tiller I had for a 1988 TRX 300 2 wheel drive. The owners son ran it low on oil and started to hear it "ticking". Long story short, the piston started to seaze and busted the skirt of the piston all the way up to the oil ring but it was still running when he loaded it onto his truck! I have the entire engine torn down and have accessed the issues and will repair/replace all parts having damage. I purchased a factory (used) Honda service manual to aid in the reassembly of the engine and have rebuilt many garden tractor engines and several auto engines so I am not new to engines but it has been close to 20 years since fooling around with motorcycle types.
I plan to use this atv for mostly driving around from farm to farm and a little playing now and then. I don't have many places to ride but i want this to be dependable and not needing much tinkering to keep it runnning good.
My main questions are with installing a new piston. I have seen kits for a Wiseco .25mm oversize piston and rings that boosts the compression to 10.25 to 1. If I use this piston will I need to rebalance the engine and would it be too much compression for the electric start. Also would this lead to overheating issues and would I need to rejet the carb or make any other changes to the engine to get it running reliably.
If this is not a good piston kit for my needs( I know Wiseco is a good brand) can you recomend a different piston kit.
I also plan to install a new timing chain, what brand should I buy and where is the best place for all the above mentioned parts.
Thank you for your help!
Dan

 

[TRX2fiveO]

If you raise the compression I would reccomend rejetting, putting in a K&N or Uni filter and possibly look into a better more brethable exhaust. Wiseco is a great piston as far as I'm concerned.


www.bikebandit.com, For all you ATV shopping needs, Factory OEM and aftermarket parts.

 

[Fastas]

i have a 1993 30 fourtrax im also rebuilding im gonan try and reuse my original piston but i will be replacing the gaskets, rings, and seals before i reinstall it. Plannign on also having it port and polished.

 

[69quadracer]

Wiseco is good, but use oem honda gaskets and other parts go to Honda or Troy they have the lowest prices i have found on factory parts just google Honda of Troy pick your brand your model and .

 

[PeppyDan]

What is the factory compression ratio for this engine? I priced the piston/rings/pin at Honda of Troy(which is only 45 miles from me) and it costs $110.90 for a .25mm oversize piston. The timing chain was definatly more money than I thought it would be at roughly the same cost as the piston assy! A coworker mentioned ServiceHonda.com for the parts is cheaper but he has never ordered anything from there. The parts do appear cheaper but has anyone dealt with them? Good or Bad ????
My coworker said that he has several trails in his area and even a shallow creek that he rides his Polaris in, so I can see this becoming more than just getting from point A to point B. I'm already thinking different tires, maybe some floorpans but need to get it running first and I just don't have the money to go crazy on it right now!
Thanks for all the help you have already given me!
Dan

 

[69quadracer]

Don't know anything about serviceHonda but would use the oem parts for original replacement they fit right and there Honda original. if your going high performance than yes after market but use name brand Wiseco,CP, J&E stay away from off the wall parts manufactures.

 

[69quadracer]

What is the factory compression ratio for this engine? I priced the piston/rings/pin at Honda of Troy(which is only 45 miles from me) and it costs $110.90 for a .25mm oversize piston. The timing chain was definatly more money than I thought it would be at roughly the same cost as the piston assy! A coworker mentioned ServiceHonda.com for the parts is cheaper but he has never ordered anything from there. The parts do appear cheaper but has anyone dealt with them? Good or Bad ????
My coworker said that he has several trails in his area and even a shallow creek that he rides his Polaris in, so I can see this becoming more than just getting from point A to point B. I'm already thinking different tires, maybe some floorpans but need to get it running first and I just don't have the money to go crazy on it right now!
Thanks for all the help you have already given me!
Dan

I think its 9to1 or 9.5 to1

 

[PeppyDan]

Thanks for the information! After some research I found that the compression ratio is 9 to 1.
Dan