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Dealers - Honda Trail Bikes

This kit includes an 88cc cylinder and piston, super head, manual clutch kit, and a high volume oil pump.

Wonder if this philly knows how famous she is, kind of like this lovely lady?

And I wonder what they look like now?

Honda Trail Bike been around since '95, and have mainly been into restoring old 50's, but a lot of the parts for those bikes apply to the newer XR/CRF50, so they sent me some motor mods including an 88cc top end and a large valve head, 20mm carb, high volume oil pump, and a manual clutch to replace the auto clutch. I would never have sprung for these on my own, but thanks to these fine folks, I can do a product review on them and let everyone know how well they work.  Riding impressions are at the bottom of the page.

I compared the HTB (honda trail bike) 88cc piston to the Takegawa piston and they are not interchangeable. The HTB  piston has a higher dome on top of the piston while the Takegawa is flat. I can only guess that its to raise compression and match the "super head". Also, you're not using your fancy cam with the super head. It is a whole different animal and a cam designed to fit a stock head ain't even close to this setup.

What's a super head? It's an aluminum replacement head that has larger valves.

I've put together a few motors now, and its not brain surgery. Line up the "T" on the flywheel with its mark, and the "O" on the cam sprocket with its mark, and that covers the cam timing. The rest is just bolting and unbolting parts. A torque wrench assures the head is tightened evenly and properly, use the cris-cross pattern,  and lining up the piston rings is something to look for. Lube everything that will move, don't wait for engine oil to get there. I took apart the manual clutch and it had a teeny bit of oil on the plates, so that might have been good enough, but for sure spread oil on the piston and cam lobes to assure no metal to metal contact. Oil film keeps the metal from touching (and bonding).

As always, you'll need to put the bike up on a stand because the footpegs and kickstand support are coming off, and remove your skid plate and rear brake lever. Give yourself plenty of room. Kickstarter and shifter come off also, and drain all the oil out of the engine. I installed the whole package here and it's logical as you'll see, parts that come off for replacement needed to come to gain access for other parts to be installed.

Before taking off the clutch cover, put a bucket under the engine. All the oil didn't come out yet. Crack off the 8mm hex screws and remove the cover. A few parts will drop out also, these are the actuator parts for the clutch that operate off the shifter. When you pulled or pushed on your shifter, you push in on the clutch and these parts are what did that.

The fun part is getting the clutch off. I had an easier time this time because I used my trusty impact driver, and I stuck a screwdriver in the gear between the primary and the clutch gear so it wouldn't budge, and the four flathead phillips screws popped right out this time. After getting the cover off, reach in and push the washer tab off the clutch retaining nut, and turn the nut off. I gave it a few taps with a punch and it turned right off. Now the clutch will slide off the crank.

The manual clutch kit comes with a new shifter arm because it doesn't need to push on the clutch any more, you're going to do that with a cable now. The shifter shaft will pull right out after you unbolt two of the items holding it on up by the shifter cog. Put in the new shaft and replace those two items and the shifter shaft is complete. No brain surgery yet. Now, before I put on the new clutch I noticed the oil pump. You wouldn't be able to access this with the clutch in the way (I think). Maybe you would, but this is definitely the right time to change that out.

For the high volume oil pump to work properly, you'll need to drill out the oil hole leading into the cylinder. They instructed me to drill a 2mm hole, but who has metric drill bits? A 5/64 bit is real close, but to get at the hole you'll need to pull off the cylinder, the head and one of the cylinder studs. Once again, another part (or series of parts) needs to come off to gain access.

Once that hole has been enlarged and you're sure no metal chips were left behind, put on the new high volume oil pump. Now you can slide on the new primary gear, clutch gear and its bushing, and the manual clutch. Before you put on the cover, make sure you have all the seals installed that they gave you. One is for the kickstarter hole, and the other goes underneath the clutch actuator arm. You need to disassemble the cover  where the actuator arm pivots and find the hole that needs the seal. Always use grease on the inside of new seals, rubber wears quickly if unlubed, but when greased it has no contact with the metal.

You're ready to put on the cover with its new gasket. The top end that you took off to get at the oil hole can be installed also and your ready to ride. Remember to give everything a nice  break-in period of about 5 or 10 minutes real easy, then about 1/2 hour of riding but not hard abuse. You need to be sure motor lube is everywhere, and if there was a sharp corner or a high spot that needed to be worked off, it did, and the metal particles have worked their way out.

Don't be afraid to get a manual clutch, and for $155 it ain't a bad buy. As soon as we crack the freezing mark and some of this snow melts I'll let you know how well it works.

Riding impression of the 88cc kitted bike.

This baby has GREAT torque, and since it has a 20mm carb, you'd figure it would have great over-rev. It does not disappoint!! I really, really like this motor. The frame that I have it in holds it back a little, but this motor is not down on power from a Takegawa kitted 88 at all, and I think it is probably stronger. The rev's seem to turn just a little slower than a Takegawa bike, but that could be the pipe or something else. I have the Big Gun pipe on this kit, and a Fast50s pipe on my Takegawa, and you've heard it before, I love that Fast50s pipe.

Riding impression of the Manual clutch

This kit works well and makes your fiddy feel like your bike bike. You can fan it a little, but I wouldn't abuse it. It doesn't look like it would hold up to a 125cc two stroke screamer rider that fans the heck out of his clutch. All my buddies that jump on this bike snub it when they don't pull in the clutch right away. The tendency on a fiddy is put it in gear and go. Even I do it once in a while. I go faster on an auto clutch believe it or not. With an auto, I get on the gas when I'm still on the brake in corners and meter the power out that way. With a clutch it's one more thing to think about, but a coordinated person would probably have no trouble.

Would I pay money for the manual clutch?

I'm sorry, but if it's a fiddy, it needs the auto clutch. Yeah, it's nice to be manual, but it's overkill in my opinion. This kit works fine once you locate a lever assembly, and make sure you keep the cable off the pipe or it will melt!

I would not pay money for this kit, put in HD springs and call it a day.

 

 

 

 

 

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