Road Toad Clutch Engagement Question ....

[Alberta Mike]

On my '76 Road Toad, the clutch engages but it engages quite late as compared to a lot of street bikes I have owned. The hand clutch lever is almost all the way released when the clutch starts to grab. I don't think I have any "slack" when I start to squeeze the lever either, but I'm not totally sure about that, I'm not sure if a person should be able to feel that slack or not. Somehow, I can't imagine a cable adjustment solving this but I might be wrong on that. As usual, any advice on how to remedy or fix this is appreciated.

[Bill2001]

On my Wombat 94, there is about 1/4" of freeplay at the hand lever. The "friction zone"-- the area between where the clutch starts to grab and where is is fully engaged-- is quite narrow, only 1/8" or so.

[Alberta Mike]

Thanks Bill. When you release the clutch lever slowly, where in your release stroke range does the engagement start? Close to the very end like mine or maybe earlier? Looking forward to your reply as well as some other responses as well.

[matt glascock]

Hi Mike, Clutch set-up in a way depends on how you intend to use the bike. On the three Hodies I have set up for racing, I've shimmed the clutch disks so as to minimize free play provided that the clutch fully engages and disengages and doesn't drag and the gears don't slip. I keep a finger on the clutch continuously and feather the clutch frequently (more so HS, but also on MX tracks). That way I don't have to compress the lever as far to slip the clutch and shift (working on that up-snick technique, but not conceptually totally cool with it yet). On play bikes, I shoot for standard free play at the clutch arm and lever and just grab a handful of clutch at all shifts. On your bike, I assume the clutch engages and disengages at approximately the same point in the stroke range of the lever. It sounds like you may need to look at shimming the clutch disk. Just a couple basics. Are your clutch friction disks and steels in spec? Is your clutch cable roached out? A nearly broke cable will cause the same clutch feel. Also, get a Wombat Official Workshop Manual. All this is explained in great detail within.

[Alberta Mike]

Hi Matt ..... to be honest, I can follow some of your explanation but in some places I get a bit lost .... but I think I get the idea. I'm guessing that on your racing bikes, your engagement/disengagement point is almost instant (little or no cable slack) so you can shift almost as soon as the clutch is squeezed, is that right?

This bike has only 1100 miles on it and I bought it in '93 at it's been in my basement since then till this spring so I would very much doubt that the cable is stretched or in need of replacement. Never been into the clutch so whether the disks and plates are within specs or not would be a mystery. Not being plated and registered and since I live in a residential area means I've just taken the occasional little trip up and down the street and am not really too familiar as to how this is working.

I guess one question at this time is this ...... in a stock bike in original condition (and not racing, etc), how much clutch hand lever release would one expect until the clutch starts to hook up? Like I mentioned in my post, this bike of mine engages when the hand lever is at least 3/4 of the way through its stroke. Does this sound right?

The one thing you mentioned were the shims. I'm not sure exactly what they do and what would be the result of adding or removing shims on what happens with the hand lever engagement/disengagement point.

Hopefully, I'm not asking too many questions at once.

[matt glascock]

In simple terms, the clutch forms the interface that allows the rotational energy of the crank shaft to be applied to the transmission to ultimately move the bike. The clutch basket spins continuously as it's mounted to the crank shaft. Inside the clutch basket there are alternating plates (friction disks and steels). The steels engage the clutch basket and the friction disks engage the transmission primary drive gear. It is the interface between these disks that ultimately transfers power from the motor to the transmission. These plates are compressed together tightly within the clutch basket by springs. When you pull in the clutch lever (disengage the clutch), that force is transmitted through the cable to a disk that in essence further compresses and subsequently counteracts the springs forcing the plates together thereby allowing the steels to spin freely without spinning the friction plates and in this manner, the rotational force of the engine is disconnected from the transmission. Conversely, when the bike is in gear, as you let out the clutch hand lever (engaging the clutch), the springs in the clutch basket smash the steels against the friction plates (which you recall engage the primary drive gear of the transmission) thus transmitting the rotational energy of the crank shaft to the transmission. Shims are subtracted between the clutch disk and the clutch basket as needed to reverse the effect of the friction disks becoming thinner through wear (or in my case, to change the free play of the clutch). What you need to establish is a balance so that when you disengage the clutch, you can shift the bike through the gears without the bike lurching and that when the clutch is engaged, there is enough force applied to the friction disks by the steels that there is no slippage of the smooth transfer of power from crank shaft to transmission. You are correct in that I set my race bikes up so that I can slip the clutch with minimal pull on the lever. Slipping the clutch is a technique that partially disengages the clutch thus unloading the engine. This is used to keep the revs of the engine in the power band even though the power of the engine is not being fully transferred to the transmission. This is a useful maneuver when going up steep hills or through deep sand when the engine would otherwise bog down. The standard free play should be about 1/4 inch meaning that disengagement of the clutch will begin after the end of the clutch lever has moved inward approximately 1/4". You are describing too much free play. Really the only way to sort out the clutch issues is to go over the system piece by piece and make sure you replace any parts that are out of spec. While not a high-mileage bike, lets face it- it is a 40+ year old bike owned by someone else who did God knows what with it. I hope this helps. PS all parts required for comprehensive repair are available from out trusty parts houses Strictly Hodaka and Hodaka-Parts. You should also try to score an official Road Toad owner manual and parts list. The exceptionally well prepared exploded parts diagrams within are very helpful.

[Alberta Mike]

OK Matt ...... I think I get it, never had a bike clutch apart but I do have an owners manual (with the parts diagrams) and I see what you refer to. Similar to say a standard tranny car with a single pressure plate and a single friction disc which couples up the engine rotation to the driveshaft right? But the bike situation is a multiple number of each of those parts?

I see in the parts diagram that the "shims" (available in different thicknesses) are on the outside on the clutch package, therefore when a person adds a shim (or shims), he is compensating for wear on the friction disk and perhaps the steels as well, correct? So the disks and steels are essentially pushed closer together once the new shim(s) are installed, is this making sense? So it would appear that in my case, the steels & disks are possibly worn which a simple cable adjustment cannot compensate for. My fix (if this was the problem) would be to add one or more shims.

Your statement ..... "The standard free play should be about 1/4 inch meaning that disengagement of the clutch will begin after the end of the clutch lever has moved inward approximately 1/4". You are describing too much free play." ....... you are saying that the clutch hand lever should start to disengage the clutch when the hand lever is pulled inwards by the operator after 1/4" of squeeze on the lever? Or are you referring to 1/4" of free movement on the clutch lever on the engine case? Either way, you are saying essentially the same thing. And mine is disengaging the clutch pack but taking much longer to happen due to disk and steel wear.

[matt glascock]

You are exactly right on all fronts with one exception. The free play on the clutch actuating arm on the clutch side case is less than 1/4". I believe free play limit there is 3/32". This discrepancy is accounted for be the movement of the cable within the cable sheath. Someone smarter than me can weigh in on the arm free play limit but 3/32" rings a bell. A simple test would be to remove the cable from the actuating arm on the clutch-side case and see how much free play there is on the arm. If within spec there, your problem may be as simple as replacing a worn, frayed clutch cable. It is also a good idea to keep a selection of shims for tweaking and adding to the system as needed or to tune it to your liking. Now to be a total buzz kill, one squirming issue always present with these bikes is a concept The Captain hipped me to - the DPO (dreaded previous owner) Syndrome. Its actually one of the fun parts of digging into a 45 year old dirt bike. Many parts that seen to fit across model lines are not strictly equivalent in dimension. You might just have an Ace 100 or Dirt Squirt clutch pack in there. All part of the fun. I found an ACE transmission (1 up/4 down) in a Dirt Squirt. Hopefully that's not the case here

[Hydraulic Jack]

I see in the parts diagram that the "shims" (available in different thicknesses) are on the outside on the clutch package, therefore when a person adds a shim (or shims), he is compensating for wear on the friction disk and perhaps the steels as well, correct? So the disks and steels are essentially pushed closer together once the new shim(s) are installed, is this making sense? So it would appear that in my case, the steels & disks are possibly worn which a simple cable adjustment cannot compensate for. My fix (if this was the problem) would be to add one or more shims.

Actually it is the other way around. As the plates wear, the clutch body moves father away from the engine and closer to the clutch side engine cover, requiring that you take out shims to compensate for wear. Clutch spring pressure pushes the whole pack toward the outside. As the plates wear and get thinner, the clutch pack moves that much farther outward in response to the springs.

So if you can't get full clutch engagement with the cable slacked, and there is no free play in the clutch actuating arm (not the hand lever) you need to remove a shim. Maybe more than one if you have several. How many shims are needed depends on where the side cover comes to rest when tightened down, so even the gasket thickness can alter clutch engagement. If you didn't use a side cover gasket, that can leave you with a slipping clutch.

[matt glascock]

OOh, I didn't read that very well and I also did a poor job of explaining it. HJ has, as always, nailed it properly. The purpose of the shims is to maintain the proper relationships between the clutch pack, disk and actuating arm. The shims, in essence, thicken the clutch disk so that it can properly disengage the clutch from the fixed position of the actuating arm regardless of the position of the clutch pack. As the clutch moves outward from the motor during the disk wear process, it becomes closer to the pivot point of the actuating arm which has a fixed range of movement. Removing a shim restores the proper relationship. I'm better doing it than describing it. Sorry for any confusion.

[Alberta Mike]

Thanks boys, if I remember 10% of what you guys know about these bikes then I could start handing out advice to others who ask questions .... ha! Seriously though, your replies are certainly appreciated.

So it would appear that I should eventually get into that clutch and take out a shim or two. By the sounds of it, the "check" as you are removing a shim (or shims) is to temporarily replace the cover case every time something is removed and check the free play on the case actuating lever, does that make sense? I don't think I want to start tearing the whole thing apart and measuring disks and plates, etc.

I noticed in the parts diagram that the clutch nut (#944014 .... M14) is a left hand thread, that could cause problems if a guy didn't know that. A friend had a Husky CR390 and the guy before him snapped the end of the crankshaft off not knowing about a LH thread on the right side of the engine where the flywheel was located on those monsters.

Being a less-than-novice bike mechanic (I have had tractor engines apart though), I need clutch repair info steps from a shop manual which appears there are none of for the Road Toad. Are there any Hodaka shop manuals for other models that would have the same procedures? I see some for sale (out of the USA) on eBay which, living in Canada, I would avoid like the plague. Getting stuff up here via eBay USA can be a nightmare sometime.

[matt glascock]

Yep, the clutch holding nut is "lefty tighty/righty loosey". That and the threads on the flywheel for attaching a fly wheel puller are the only left hand threaded features on the bike. I'm glad you discovered that fact in a much cooler way than your friend (and ME!!...oops). Regarding shop manuals, PABATCO produced them up to, but not into the painted tank era. Fortunately, many of the operating systems persisted so that much information is applicable to the later models. Strictly Hodaka sells both "Official Workshop Manuals" which are invaluable resources for maintaining your bike. I use both frequently. One volume covers Ace 90, 100, 100B, and MX (Super Rat) while the other covers chrome tank Wombats and the Combat Wombat. If you can afford both, get both. They are really well written and helpful.

[Alberta Mike]

1) So then, either of those manuals (both preferably) would have my clutch issue procedures necessary for a '76 Road Toad? That's all I really need for now anyways I think (hope).

OK, I will do some more checking north of the border up here, there is an old bike shop locally that used to sell Hodaka stuff many many years ago in the 70's, the old guy is in the place now and then, I'll see if he might have something kicking around. like I said earlier, eBay stuff coming out of the USA is sometimes more than painful, and sometimes the carrier arrives at the door with some unexpected costs, especially UPS.

You mentioned the left hand threads ...... I can see the reason on a right side clutch (or in the case of the Husky the flywheel) but why would the left side flywheel puller anchor threads be left hand I wonder, that confuses me? If we get into that, I'll be spinning though.

2) Is there anything tricky about removing the clutch cover (with regards to the oil pump assembly, etc) that a guy might be aware of?

3) And when you do clutch work, do you use gasket cement or some such product when reassembling?

[matt glascock]

The fly wheel pulling tool (which you will need - there is no good substitute) is a two-part affair. The outer part threads into the fly wheel (LH threaded) and the inner part threads into the outer part (RH threads). First, you snug the outer part into the fly wheel. The inner part, which is basically a large bolt is then threaded in and tightened. As this progresses, the inner bolt begins to abut the crank shaft. As it is further tightened, it begins to force the fly wheel off the crank shaft. You need the opposing forces of the outer part maintaining counter clockwise force on the flywheel so that you can exert clockwise force on the inner bolt which is ultimately the force that presses the fly wheel off the crank shaft. You don't need to disassemble the oil pump to get to the clutch. You do have to remove the oil pump cover to get to the rearward clutch cover bolt. I just oil the gasket well before reassembly. You'll want to drain the oil before removal of the clutch cover (wet clutch, very messy if you don't first drain the oil. Either manual would provide valuable information regarding clutch procedures. One additional bit - there is a small metal cylinder (pressure piece) that links the clutch arm to the disk. It sits unattached in a well in the clutch cover and is prone to loss. Keep your eyes on it during removal and hold it in place with a dab of heavy grease during reassembly. The clutch mechanism won't work without it. Its also good to keep the kick starter lever down and out of the way during the removal process.

[Hydraulic Jack]

It should be possible to remove the clutch side cover without draining the transmission, by laying the bike down flat on the left side. Depends on what you are doing and how long it will take. If all you want to do is verify the shim stack or replace control rod springs, you can lay it down and save your oil. I would empty the carb bowl first, but it can be done. If you plan to overhaul the clutch, I would drain the oil and toss it.

Not all flywheel pullers have opposing threads. The Hodaka puller does. Best practice is to inset the outer piece left hand threads fully into the flywheel, and then use the inner screw to drive off the flywheel while holding the outer piece with a wrench, rather than hanging on to the flywheel and cranking down on the screw. If you hold the large insert with a wrench, it really doesn't matter which kind of threads were used. Hodaka chose to use opposing threads. They probably had a reason, and it may have been as simple as those were the threads that came on that outsourced flywheel.

[Alberta Mike]

Matt ..... you mentioned a part as follows ..... "One additional bit - there is a small metal cylinder (pressure piece) that links the clutch arm to the disk. It sits unattached in a well in the clutch cover and is prone to loss. Keep your eyes on it during removal and hold it in place with a dab of heavy grease during reassembly."

I have the parts manual here, can you specify what the part number is (or the number indicated on the parts diagram)? If I can spot it in the diagram, it might be easier to spot when removing the clutch cover, That is assuming that it is in the factory diagram.

[Hydraulic Jack]

Clutch pressure piece. Looks like a roller bearing, and probably is one.

https://www.strictlyhodaka.com/product- ... 7_02rt.htm

Part number 68 on Figure A, 02 Toad.

[matt glascock]

Yep, that's the one. Kelly McKiernan came up with a slick trick to keep it in place during the cover removal process. He used a rare earth magnet on the clutch arm to magnetize the pressure piece thus keeping it in place. He published a video of the technique on his socalhodaka youtube channel where he replaced the kick crank on a Super Rat. Its a really well-made video tutorial and worth a look. The pressure piece is in fact a roller bearing. It is the exact same part used as the kick rollers in the starting mechanisms of several models. Also, as Hydraulic Jack pointed out, you can lay the bike over on the left hand side for these procedures. If you do so, one bit of advice. Use a block (4x4, log, etc.) to provide relief for the shifter mechanism to avoid tweaking it (credit to Captain Eddie for that suggestion).

[Alberta Mike]

Thanks Boys ..... more good info !!!