Bought a TRX70 and need to learn about them

[Blown 331]

I've got around 20 Honda 70s and picked up my first TRX70 a few days ago. My dad saw it in the local paper for $100 bucks! It was just over 10 miles from my house so I picked it up and just paid asking price.
I only spent about 15 minutes messing with it but I've already noticed its quite a bit different than an ATC70. So rather than reinvent the wheel I'm hoping you guys can teach me about them. Its also got a Clarke plastic gas tank. Would the original tank have been metal or plastic?
It doesn't have spark. I pulled the recoil- wow that thing is different. I looked through the flywheel and didn't see points or a lighting coil. I pulled the flywheel and it wouldn't come off through the cover like it does on an ATC, that sucks. I had other things to do so I didn't go any farther. Is there a common spark issue with these? I saw one on craigslist and the seller said he had to replace the "electronic box". I'm assuming that means ignition module, is that common at all? Any other comments or suggestions are appriciated.

http://i1041.photobucket.com/albums/b411/Blown_331/trx70.jpg

http://i1041.photobucket.com/albums/b411/Blown_331/atctrx70.jpg

[hublake]

Seeing that you have alot of 70s, I would just forget about the trx and I will give you triple for what you paid for it and come and get it. lol

[MonroeMike]

Service data.
http://www.3wheelerworld.com/showthread.php/126393-ATC70-TRX70-Service-Data

[Blown 331]

Seeing that you have alot of 70s, I would just forget about the trx and I will give you triple for what you paid for it and come and get it. lol

You're not the first to make similar offers!


Service data.
http://www.3wheelerworld.com/showthread.php/126393-ATC70-TRX70-Service-Data

Sweet thanks. I printed the pages on testing the ignition system. I did a little looking and coils are dirt cheap. The module is discontinued and usually costs more than I paid for the bike. I think at that point it would be getting an ATC ignition system, I have spares.

[KASEY]

the atc flywheel won't fit it... the taper is different i have a spare cdi box if interested... PM for details

[Blown 331]

the atc flywheel won't fit it... the taper is different i have a spare cdi box if interested... PM for details

Wow, these thing are really different than the ATC's. I need to trouble shoot it first then I will let you know on that module. Thanks! But hopefully its not needed. Any idea if I could get an XR70 module on there? I have one so I can always check that out when I get home and they are dirt cheap.

[Vealmonkey]

The original trx70 tanks are black plastic and were under the front fenders. They are cdi and parts are getting hard to get as they were only made 2 years. If it doesn't have a rear brake pedal, it's an 86, the 87s' having the rear brake pedal. The sidecover and recoil is different from an atc70. The rear mounts and frame and seat are different from an atc70. They are kind of neat but nowhere near as neat as the aftermarket quad set ups for an atc70 frame. Still alot of fun. Will still take lifan engines. Enjoy your new machine. Add a lifan engine and use the sidecover and recoil to do a pull start conversion on a 125 or larger lifan. Make a custom pipe. Hold on and have fun.

[Blown 331]

Thanks for the info! It does not have a rear brake pedal, the serial tag is intact and says 1986. I'm not a Lifan guy, so thats out for me. Yeah I'm one of those. lol.
I've got an XR70 and the CDI units will interchange but when I did that neither bike had spark. I tested the TRX70 module according to the specs in an above post and it fails. Crap. But for some reason I'm not real confident in the test. My coil and pick up definitely pass. And all connections look good. I also pulled the flywheel and cleaned everything up. I'm going to post a wanted add on craigslist for a parts bike. There are a few close to me now but they are always big money (other than the one I got). I also have a late 80s TRX300 CDI I may try.

[Blown 331]

Alright I came up with like 5 CDI boxes that will plug in and still no spark. I also found testing procedures for the stator and that also fails. It says resistance between the black/red wire to gournd should be 464 to 696 ohms. I'm reading open. If I switch the meter to k ohms I get 625 (meaningless I know).
So here's my plan and I'd like some opinions on this. I took my TRX70 flywheel and put it on my 2000 XR50 and it ran great. So that tells me I could just buy a XR50 stator plate with stator and pick up and it will work. An XR50 CDI box will plug into the TRX harness as well. So I'm thinking of buying this XR50 CDI for $19 shipped. http://www.ebay.com/itm/2005-HONDA-CRF50-XR50-CRF-XR-50-CDI-ECU-ECM-COMPUTER-BRAIN-1-/270971809437?pt=Motors_ATV_Parts_Accessories&hash=item3f172dae9d&vxp=mtr And this XR50 stator plate for $20 shipped. http://www.ebay.com/itm/IGNITION-STATOR-MAGNETO-PLATE-90CC-110CC-125CC-150CC-CRF50-CRF-XR50-IS01-/330725181380?pt=Motorcycles_Parts_Accessories&hash=item4d00c1c7c4&vxp=mtr I'm thinking I sould be good to go then. Thoughts?

[KASEY]

50 AND 70 HAVE A DIFFERENT STROKE this might have an effect on timing and advance,, it probably will run but,,,,, just saying...

[Blown 331]

I just looked up the part numbers for every piece of the ignition system using Dillon Honda's parts look up webiste. Its all the same part numbers for a 2000 XR50 vs a 2000 XR70. So I should be good I'm thinking.

[Blown 331]

I'm going to post a wanted add on craigslist for a parts bike.

Well this yielded another but its quite the pile. lol. Another 1986. Runs great. I suspected it was an ATC motor and it is. It does shift all up, so I'm guessing 1985 ATC70 engine.
I told the seller I thought it was an ATC motor and would have points but he pointed out the ignition module. I pulled the module and it still ran. lol. I tried the module on my 1st one, still no spark. I have the newer XR50 stuff on the way though. This 2nd one also has ATC70 seat and fenders and kill switch. This second one also has working front brakes. My first one is missing the cables which are expensive. And my first one has black wheels which I don't like and my rear tires leak down. I may just kill this 2nd one and put the parts into my first TRX and put together another ATC70. Not sure yet. I paid $200 for this one. Its more than I wanted to pay but he wouldn't go any lower, beggers cant be choosers and I guess I can't complain about $200 for a running Honda 70.
http://i1041.photobucket.com/albums/b411/Blown_331/trx702.jpg

[Buster Brown]

My '87 70 also had no spark...
Check your neutral safety switch under the flywheel cover. I just grounded the yellow lead to the engine and bingo.... (bypassed)

[Blown 331]

My '87 70 also had no spark...
Check your neutral safety switch under the flywheel cover. I just grounded the yellow lead to the engine and bingo.... (bypassed)

Well I can't believe it but that was the problem! The neutral safety switches do nothing on my other 70s but they are almost all points bike. All my points bikes start in gear.
I'm not sure how I came up with a open stator either. My 2nd TRX has a ATC motor but the CDI was still on it. Both of my CDI's are good and I only have one bike that uses one so now I have a spare. I also have a spare CDI for my XR50 or XR70 now as I bought one and didn't need it. And I also have a china stator and pick up. This has a lighting coil and my XR50 and XR70 do not so I could use it to put lights on either of those but I don't really have an interest in that.
I swapped wheels and tires and front brake cables from the 2nd one to the first. The first one is now totally good to go. It starts and runs great, everything works and no parts are missing. I'm still not sure what to do with the 2nd one. Probably use a few parts to put together another ATC70 then just keep whats left for parts.