*Chain tensioner on top of chain: This is a totally crude set-up, and any tensioner should NEVER be on top of the chain! This is the stressed portion of the chain, NOT where the tensioner is correct. The lower tensioner is at least (in addition to being positioned correctly) doesn't look like made in a high school shop class.*

After 1 year of adjusting the chain tension pulley then I finally bought the spring tension and continued to have problems I finally read the previous comments, FIXED- put the spring tensioner on the bottom frame under the chain which returns to the motor NOT above which goes from motor to rear sprocket like I had it and kept having chains misaligned and comming off constantly. Bottom-Good Top-Bad (That is all, Carry On) Lol

Great video. I just got the chain tensioner awhile ago in the mail and a lot of other stuff. I think all your products work very well so far. It is a good product.

Thanks for the straight up delivery, very good video. Thanks again!!!!

Do not install the rear tensioner on the top. This may look nice when peddling on a bike stand...it does NOT work in properly tensioning the chain while riding under engine power. The tension needs to be applied to the return section of chain.

We need more KZfaq channels dedicated to motorized bikes.

Love these types of videos. Your video and editing quality is just stunning. Keep it up BikeBerry.

How tight do ya tighten the two bolts and nuts. Surely don't keep like was sent , way loose. Also I lost that ball bearing is it the same size as the actuator bearing that was already in there if not I'll probably just have to adjust the clutch makeup for

Does this pully set up go for all bike

chain popping off is why I went electric. .. batteries is why I want to go back gas

The spring that came with my upgrade chain tensioner was too weak. I used a stronger spring. BTW I also had to upgrade my chain because it was too weak. My issue that I have now is that my chain locks up over the small gear that has the cover over the bucking bar. When this locks up it stretches my heavy duty spring. Worst case, the chain jumps the rear pulley and damages a few spokes. I need to solve the issue of the locking chain and also align the chain on both pulleys. Any thoughts?

Do these work on a 49cc 2 stroke gas scooter??

is there a 4 stroke transmission version of this? EDIT: i mean the second one. the first would obviously work on any chain.

yeah I wanna see a full jackshaft install

Thanks for the video. I was totally stumped

I like #2 ...Im gonna get one!!

What about your dual pulley version why no video for that?

Is there an engine mounted spring loaded chain tensioner for the 4 strokes? Or would this one work with it?

Just installed the billet tensioner with a new 415 chain. Do you also need the rear idler pulley . still haveing alot of chain slap and popping off.

? why are you mounting the tensioner to the top of he chain? after seeing this, and your video of the spoke bending clamp on sprocket I'm starting to wonder about you guys o.O ...

Can you show us new upgrade parts like cylinder heads and other

Cool

The spring chain tensioners provide good tension and alignment when the bike is started but they let your chain get too loose during start-up unless the chain is tight enough on it's own to stay on without a tensioner. The thing about the stock tensioner is that it stays in place for the most part.

Seriously, this video should be pulled. Or have a huge subtitle warning "caution...do not mount tensioner here cuz it don't work". It has to be mounted on the bottom section of chain.

Nope. Never install a tensioner on the power side of the chain. Always on the return side

0:43 an obvious issue. when you hit the throttle the spring is going to let out, the chain doesn't get shorter. all of a sudden all of the slack in your chain will be spooled out. it is an issue in all circumstances due to wear and tear, but in some circumstances, like if the bike already works without a tensioner/idler in the first place but just has a few chain issues this might help, but even then you will be spooling out your chain to the bottom of the sprockets, so if you turn while that happens the slack will lean, and like how the derailleur on a normal bike chain works, it will walk off of the sprocket. in other words, NEVER DO WHAT IS IN THE IMAGE AT 0:43. you have to maintain the leading edge into the power receiving sprocket (the sprocket that receives the power), that is what the idler/tensioner is for. to put is bluntly, never tension the top of your chain unless it is rigid and cannot be moved, by a sledge hammer. int he case of that image it probably worked on that bike built to receive a motor, because the chain probably was basically tight enough already to use before you added the tensioner. that isn't true most of the time, and using a half link is more of a hack than a solution. it works, but in general you shouldn't have to.

i cannot attach my tank on the frame because there are the brake cables. do you have for me a tipp ?

I find the arched tensioner ( like an alternator bracket ) is much better than any spring tensioner with only the plastic wheel to wear out , and then I went to the bearing / washer style wheel so no more plastics to replace . C'mon bikeberry , you can do better on such an important issue .

work better if you tension the bottom of the chain instead of the top

From the first example

i dont undrstnd how to do 16:1 fuel mixture help please

FYI, if you buy the billet spring tensioner, they don't give you the bolts, or ball bearing. So good luck finding those yourself

It can still move back and forth

Holy dog ____Batman. Putting your tensioner on top like that is extremely dangerous. If bikeberry doesn't realize that they're in the wrong business for sure.

What do you do if your gas tank gets a dent in it? My bike fell over in strong wind.

#1 seems like a bad idea. The bottom part of chain needs the tension and aiming to feed the input correctly. The sloppy bottom chain will jump the sprocket if not straight and aimed correctly..

3:23 thats an downgrade!

CHAIN TENSIONER SHOULD BE MOUNTED TO REDUCE CHAIN SLACK ON THE BOTTOM LOWER PART OF CHAIN NEVER EVER ON THE TOP.! THE UPPER PORTION OF CHAIN WHEN UNDER POWER IS NATURALLY PULLED TIGHT AND WHEN COASTING OR DECELERATING GETS LOOSE . PUTTING TENSIONER ON TOP WOULD CAUSE TENSIONER TO BOUNCE WILDLY DEPENDING ON ENGINE POWER LOAD ON CHAIN. (CHAIN SNAPPING BACK AND FORTH DEPENDENT ON LOAD) THE TENSIONER SHOULD BE INSTALLED ON BOTTOM WHICH IS NOT UNDER POWER LOAD AND IS MERELY ALONG FOR THE RIDE.

The top pully is point less

The first example is in my opinion wrong, on the side where the chain is pulled by the engine one should have the chain straight. I have the tensioner on opposite side like an a normal bike. Just like the second example.

To everyone with a brain 🤪 if your bike doesn’t have rear suspension you probably don’t need a tensioner if the chain is shortened to fit properly then a spring loaded tensioner works great to cure chain slop upon acceleration deceleration. Oh don’t mount anything on top of the chain which should be a straight line sprocket to sprocket never impede horsepower before it’s used

spring is not strong enough bought one myself how to replace the spring what a disappointment

The top drive of the chain is already under tension it's the bottom chain that needs the tension

If you don't have a drill borrow one

*comment about tensioning the wrong side of the chain here*

Putting the tensioner on the top doesn't make good sense. Look what happens to the slop on the bottom side of chain when pull is applied.

Tensioner should be on the feed side of the chain, not the drive side!

Chain tensioner is in the wrong spot there . It should be on the bottom

The chain tensioner goes on the non-driven part of the chain, the lower chain. This video is wrong wrong wrong. Your chain will keep popping off if you put the tensioner on the upper driven part of the chain.

??

NO NO NO The tensioner shouid always be at the bottom!!!

OMG, seriously?! You are instructing people to mount the spring loaded guide on the tensioned side of the chain? For your own good, I hope nobody gets hurt...

bye bye chain guard.

Ok ppl: When using spring loaded tensioners, YOU WILL NEED BOTH if you want to start a 2 stroke engine. One underneath the chain to keep tension while the engine is running One on top of the chain to keep tension when starting the engine

The trick is...Wiff.

I wouldn't trust the 1st tensioner

Lmao they seriously installed a chain tensioner on the top chain? A website this professional should know that is a terrible idea. You are supposed to prevent the bottom chain from slacking, all your torque is put on the top chain that is going to be taught at all times while the bottom chain slap around violently.

Do you NEED a chain tensioner?

Sorry but that's a stupid place to put it... Why not just have it on the bottom part of the chain? You'll just have the bottom go slack when you're driving because the top of the chain is the one the engine is pulling.

You lost all respect in that you can't put the tensioner on the top. If so it will have to pull all the slack out of the chain before the bike will move. You demoed it by peddling while on a kick stand, but in actual operation it absolutely won't work that way.

So much wrong with this video. I hope no one has followed this tutorial over the years. The 2 main issues is the mounting location of the tensioner and the brakes being used on this bike. First, you never mount the tensioner to the seat stay. The top of the chain is where the torque from the engine is transferred to the rear sprocket. This will exert more force on the tensioner than it was designed for. Not only that, the top of the chain tightens under acceleration anyway. The chain stay is where this tensioner should be mounted. The bottom of the chain doesn’t have any force transferred through it from the engine and it does get looser under acceleration. Second, you are using rim brakes on a mag wheel. This is not advised. Rim brakes can result in premature wear and could lead to rim failure. Mag/alloy wheels really should be used with disc brakes.

You don't know what you are doing. Tensioner goes on the bottom.

tensioning the loaded leg of the chain is absolute stupidity. you tension the feed side, not the load side... that spring is just absorbing and dissipating energy that is supposed to be doing work. christ on a crutch, is this what our schools are producing these days?

wtf! tenssioners need to go on bottom chain not top

Chain tensioners ALWAYS go on the slack side of the chain and not the drive side... This video makes you guys look like idiots. I suggest pulling this video, and make a video installing a tensioner properly. Edit: I just pulled up your video "The Beast 79cc 4 stroke engine", and the tensioner is installed properly on that bike...

This is a horrible video! You never put a chain tensioner on the drive side! Period! Now you have all kinds of crazy forces action on the poor thing from the motor drive side. always put a chain tensioner guys on the return side going back to the motor. There is no forces acting on the tensioner that will cause you a bad day! It will just run the slack out of the chain and that way there is not drive force on the Tensioner! !

DON'T BUY FROM THEM!!! THERE A RIP OFF!!!! MY CHEAP EBAY MOTOR KIT IS WAY BETTER, AND FASTER THAN THERE STAGE 3 KIT!!!

Issue: why would you put the pulley on the top chain where that is where the chain is pulled? The top chain should be taught and the bottom chain needs the tensioning. IF you do it this way the bottom chain is loose.