I think I have had a roller cam follower come apart.

[Bill Hilly]

I have ran the wheels off my Hawk every since I got it, but especially after warning the motor up. I have put about 2,500 miles on it since doing the motor some months ago. It's performed great, but today, as I was getting ready to park at Walmart, I heard two little metallic pings within seconds of each other. I thought it sounded like I ran over something, then as I was pulling into a parking spot , the motor got noisy, almost like a loud clicking, almost like a card in a bicycle spokes, but louder. I made absolutely sure that I hadn't lost oil, and drove it home on the back roads, about 6 miles, or so. I didn't try to make much power, but the motor ran alright, and would get noisier, and quieter, and occasionally act like the chain , or a transmission gear would jump a tooth. I figured it was probably a transmission issue, at worst, or the centrifugal oil filter coming loose at best. I figured I would pull the valve cover, before taking side cases off, and my exhaust valve has at least an 1/8th inch, or possibly 3/16th inch of clearance. I keep the valves adjusted regularly, and the locknut is still tight, everything looks normal under the valve cover, other than the exhaust valve having too much clearance. I have a feeling it would be a mistake to adjust the valve, and try starting it. I don't think the bike would have started good, or ran decent if the exhaust valve wasn't seating right, so the only thing I can figure is a bent pushrod, or the roller wheel coming off the follower. The bike was just at a slow unstressed speed when it happened. I think it's the roller, because I think that bouncing around in the works was probably my noise.
It's miserably hot here, so I may just slap the stock motor from my parts bike on it for now. I honestly have been thinking about selling either the Hawk, or KPX, because they both get used in about the same way now. I almost regretted doing the motor, and gearing, and tire type changes to the Hawk, because I got the KPX to be more if a road bike, with the knowledge that the Hawk was more of a back road bike, BUT, I ended up using it exactly like the KPX. I probably will eventually fix my warmed up motor, but I won't be in too much hurry. I will probably also go back to knobbies on the Hawk when the 50/50 tires wear out.
I am grateful it happened before I put it up for sale, because if someone had bought it, and it had engine trouble soon after, They would think I was a crook. LOL

[Megadan]

The only way to really know would be to take things apart. If the roller follower roller did collapse it would be pretty obvious. Motocult sells the WGK roller followers, but be warned they are not cheap compared to the random cheap ones you can find on ebay or aliexpress. https://motocultparts.com/products/u...43550418206919

Thankfully, so far, I haven't had a problem with mine even with the big duration cam I am using.

[Bill Hilly]

Originally Posted by Megadan

The only way to really know would be to take things apart. If the roller follower roller did collapse it would be pretty obvious. Motocult sells the WGK roller followers, but be warned they are not cheap compared to the random cheap ones you can find on ebay or aliexpress. https://motocultparts.com/products/u...43550418206919

Thankfully, so far, I haven't had a problem with mine even with the big duration cam I am using.

I also have a long duration cam, and was on the fence about using the cheap roller followers. I may tear into it some in the morning. If I do end up repairing it, I will be ordering a thin head gasket from MotoCult for the 70mm bore, because to my surprise the 70mm kit from AliExpress came with a stock like gasket. Most people in the Facebook groups seem to have i damage to other motor parts though. About a month ago, I came out of a back road right at the bottom of a big long steep hill out on the main road , and I was accelerating hard, and it seemed like the chain slipped on the sprockets, in probably 3rd, or 4th but hooked back up when I eased up on it. I just chalked it up to a loose chain, which it probably was, but after I had the trouble today, it felt like that a couple times. That's why I thought it was probably a transmission issue at first. The only thing I really spent on was the 70 mm CG300( actual 250cc) kit, around $75.00. The cam,cans followers were very cheap, but I can't remember how much, but they actually cost me nothing, because they had evidently got lost in the mail. I got refunded, and then a couple weeks later they showed up. The cam gear had no dot, but I counted teeth from the pin slot. The followers had several letters stamped on them, but I can't remember what they were. Before I put too much money in the motor, I would probably convert to the OHC motor that it seems like several people are running in Hawks now, but I really don't need a 6 speed 75 mph Hawk. I really didn't need anything more than the internally stock motor, and 16/46 sprockets, and knobby tires, because I already had the KPX, but one thing led to another, the extra power led to higher gearing, and more speed, which led to milder tires, which led to the bike becoming something that I didn't need . I think I liked the fact that it seemed nearly as capable as the KPX on the main roads, but I was happy with the bike before hopping it up. My initial goal was just to have a little better power for the occasional long fast hills, that would sometimes big the bike down some. If I were under 200 lbs, or lived in flatter county, I couldn't really complain at all about a stock 229 cc motor, with about a 17/46 sprocket set up.

[Megadan]

Originally Posted by Bill Hilly

I also have a long duration cam, and was on the fence about using the cheap roller followers. I may tear into it some in the morning. If I do end up repairing it, I will be ordering a thin head gasket from MotoCult for the 70mm bore, because to my surprise the 70mm kit from AliExpress came with a stock like gasket. Most people in the Facebook groups seem to have i damage to other motor parts though. About a month ago, I came out of a back road right at the bottom of a big long steep hill out on the main road , and I was accelerating hard, and it seemed like the chain slipped on the sprockets, in probably 3rd, or 4th but hooked back up when I eased up on it. I just chalked it up to a loose chain, which it probably was, but after I had the trouble today, it felt like that a couple times. That's why I thought it was probably a transmission issue at first. The only thing I really spent on was the 70 mm CG300( actual 250cc) kit, around $75.00. The cam,cans followers were very cheap, but I can't remember how much, but they actually cost me nothing, because they had evidently got lost in the mail. I got refunded, and then a couple weeks later they showed up. The cam gear had no dot, but I counted teeth from the pin slot. The followers had several letters stamped on them, but I can't remember what they were. Before I put too much money in the motor, I would probably convert to the OHC motor that it seems like several people are running in Hawks now, but I really don't need a 6 speed 75 mph Hawk. I really didn't need anything more than the internally stock motor, and 16/46 sprockets, and knobby tires, because I already had the KPX, but one thing led to another, the extra power led to higher gearing, and more speed, which led to milder tires, which led to the bike becoming something that I didn't need . I think I liked the fact that it seemed nearly as capable as the KPX on the main roads, but I was happy with the bike before hopping it up. My initial goal was just to have a little better power for the occasional long fast hills, that would sometimes big the bike down some. If I were under 200 lbs, or lived in flatter county, I couldn't really complain at all about a stock 229 cc motor, with about a 17/46 sprocket set up.

You already have a KPX, so doing that swap on a Hawk just seems like a lot of work for no reason. I would just figure out this failure/problem and get it back up and running. Maybe look into the clutch springs, or check the shift ratchet (also on that side) and make sure it's not bent and engaged properly. Possible you aren't going all he way into gear and it's slipping out because of it.

[Bill Hilly]

Originally Posted by Megadan

You already have a KPX, so doing that swap on a Hawk just seems like a lot of work for no reason. I would just figure out this failure/problem and get it back up and running. Maybe look into the clutch springs, or check the shift ratchet (also on that side) and make sure it's not bent and engaged properly. Possible you aren't going all he way into gear and it's slipping out because of it.

I don't intend to swap to the OHC, but was just making the point that ,if I was going to spend much on one, that would probably be the best choice. I will take the push rod out first , and then probably take the top end off, if it's not bent, but I don't think a bent pushrod would cause the clicking noise. I still think the Hawk is the best deal, I ever got an a bike. It's a 2016, that I bought a couple years ago for $600.00 dollars, with , I'm thinking less than 100 miles. It was stored in a shipping container, and had a flat front tire, and a dead battery, but the tire never leaked again, and I ran it till the tires needed replaced, and the battery was alright., after it charged. I had recently replaced the battery in my TBR7, before I sold it, so I did switch batteries then, but it was still working. I chose to keep the Hawk over the TBR7, because there was just something about the Hawk, that I can't really put my finger on. I just favored it to the much nicer looking, and newer TBR7D.

[Bill Hilly]

It is the cam follower, and it's chewed up my cam gear, and almost certainly the crank gear. I would guess the time I was accelerating hard, climbing the hill, and thought the chain skipped a little was actually the first bearing coming out, and going through the cam, and crank gears, and yesterday the rest came out.

[Megadan]

That sucks. This is the first roller follower failure I have seen.

On the plus side, the cam and crank gears are cheap. You can also remove the gear on the crank without splitting the cases. It will take an interesting gear puller with longer arms but a narrow width, but it can be removed. Just make sure to put the key facing 12 o'clock so it doesn't fall into the case.

[XLsior]

I tried the rollers on a stock cam...
they were quieter at idle and cold start but unnoticeable when riding/operational.


I went back to stock flat followers after seeing witness marks on the cam which I put down to the increased reciprocating mass of the roller heads...They were DYNOP aliexpress brand...


I felt no performance gain using them. If anything it felt like I lost power at the top end. So made the recommendation to others not to use them with the stock cam along with the fact the stock pushrods were to long...which meant either shorter rods or shimming up the valve rocker assembly.

[Bill Hilly]

Originally Posted by Megadan

That sucks. This is the first roller follower failure I have seen.

On the plus side, the cam and crank gears are cheap. You can also remove the gear on the crank without splitting the cases. It will take an interesting gear puller with longer arms but a narrow width, but it can be removed. Just make sure to put the key facing 12 o'clock so it doesn't fall into the case.

I will probably repair it one day, but for now, I just put the stock motor from my parts bike on it. It's been abused, but only reads about 700 miles on the stock speed O of the parts bike. I changed the oil in it using cheap Rotella T4, and will be adjusting the valves before riding it next. I was going to run it with my modified stock exhaust, but I didn't want to take time, and cut out a gasket were the sanitary clamps hooks the middle together, so I'm using the aftermarket exhaust for now. I really didn't realize how much louder my modified motor was than stock, but the exhaust is not nearly as loud on this motor. I went for a run up the road, and was running over 55 very easily, but the road was flat. I can really tell the difference in power, and may put my 16 tooth front sprocket back on, but I'm going to give the 17 a chance, because I have a slightly smaller rear 4.60x 18" tire on it now, and the last time I tried a 17 with a stock motor, it had the larger diameter knobbies, so it may be better to use the 17. I ran about 11, or 12 miles, some main roads,and some gravel, and I think I will be satisfied, at least till cooler weather.

[Megadan]

Originally Posted by XLsior

I tried the rollers on a stock cam...
they were quieter at idle and cold start but unnoticeable when riding/operational.


I went back to stock flat followers after seeing witness marks on the cam which I put down to the increased reciprocating mass of the roller heads...They were DYNOP aliexpress brand...


I felt no performance gain using them. If anything it felt like I lost power at the top end. So made the recommendation to others not to use them with the stock cam along with the fact the stock pushrods were to long...which meant either shorter rods or shimming up the valve rocker assembly.

There is no performance gain from them. What it really helps with is the reduced need for zinc in the oil. The valves are so loud anyway I doubt anybody could hear a diference in noise level.

The pushrod problem is interesting. I notied no difference on mine.

[XLsior]

The pushrod length seemed only an issue with a stock cam. I compared the cam that came with the rollers as the kit to the stock cam after dissambly and found the supplied cam to be smaller overall with less lift and rounder profile...


the issue with was valve adjusters went out with stock pushrods.