Hi everyone, i bought a doodlebug 6.5hp kit about a year ago and now that its getting warmer i wanna be able to ride it, the problem i still havent corrected is that the chain keeps breaking off at the master link due to more power and tension i imagine. I have played around with the tension a thousand times it would seem and yet the flimsy masterlinks refuse to hold, ive even tried putting on the masterlink the wrong way to see if it would hold and still it breaks. If any of you guys have any ideas on how i can fix this issue let me know, im thinking i might just get a bigger cluth and bigger chain.
I'm of the mind that it would be hard to break a chain due to 6.5 HP when it has a centrifugal clutch. No way to shock load the drive system. So it is not the super HP that is doing it. Gotta be something else. Are you putting the sidebar on the connecting link? I know that sounds silly to ask but I've seen that done.
What is a doodlebug 6.5 HP "kit". I don't understand what the kit thing refers to.
What is a doodlebug 6.5 HP "kit". I don't understand what the kit thing refers to.
get some of that rlv performance chain the gold on gold it's good stuff.I've got an 18 hp clone on my doodle bug and never had a problem with it. if that don't fix it it's probably an alignment issue. remember the master link is the weakest link in the chain so it is usually the one to break if there is a problem
Not trying to be a smart ass but the fact that I worked as a mechanical engineer for the better part of 40 years, largely in mechanical power transmission, makes it difficult for me to believe that even the cheapest chain, or the connecting link, could be snapped using a tiny 6.5 HP gas motor coupled through a 'cushy' drive coupling such as a centrifugal clutch. As mentioned above, there is no way to "shock load" the chain under that circumstance. Going to a High Zoot chain will change nothing has been my experience. Where is that anyone has seen published specs [from a manufacturer not a parts seller] that a 'kart' chain is stronger than a C.H. INA chain? Longer lasting? Sure. Higher tensile? Doubtful.
Oldsalt i having to go with you on this one . with all the dum stuff i have done never seen a chain snap . short of some mechanical problem rocks in the chain, bent tooth on sprocket . even when i ran my dirt bike in to a barbed wire fence and wrapped the wire in the chain and me , i did not break the chain . the only time i have seen drive chains snap is . chain is shot all to hell like nothing left and a pin finely gives out . or on some big dum slow machine with 60 hp 440 volt motors with a 50 to 1 gear down ,when the line jams up tight and the over load dont trip .
other then that i can only think of one chain that snapped with out a reason, and that we were thinking went throw a fire or was some kind of really old old stuff like forge able castings off some horse drawn stuff .it was brittle as hell but no idea why:shrug:
other then that i can only think of one chain that snapped with out a reason, and that we were thinking went throw a fire or was some kind of really old old stuff like forge able castings off some horse drawn stuff .it was brittle as hell but no idea why:shrug:
at a certain point those clutches lock up. so your telling me that if your spinning the tire in the dirt and then hit the pavement you can't shock load the chain. I'm talking about high performance engine thats spins upwards of 8 thound rpm's if the clutch locks at 3 thousand i would think you can shock load the chain doing that. I'm not an mechanical eng. so I could be wrong. if so explain. I'm always willing to learn.
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You are suggesting what at first glance would appear to be a really extreme situation. The fact that the clutch is engaged, and I trust we are agreed on a normal centrifugal clutch, when the tire leaves the dirt and hits the concrete it will have very little traction...it will just continue to burn. I'm not going to get into co-efficient of friction and how it relates to unit pressure and surface speed but take my word for it, the tire will not seize to the concrete and break a chain, it will just continue to "fail to hook up". Also, even if it would seriously increase the the load on the tensioned strand of chain the clutch would surely slip before it could break the chain. Bottom line; a regular minibike tire cannot be counted on to supply enough traction to break a chain...and I'm thinking a little centrifugal clutch does not have enough grip to make it happen if in fact the little tire could be properly hooked up.
A master link [properly called a connecting link] is not really all that much a 'weak link'. The pins and side bars are of the same size and material. Unless the application is for a very high speed chain drive [which will almost certainly require special lubrication such as spray or sump] there is no reason to worry about a standard connecting link.
I have run into only one instance where a two wheeler utilizing a chain on the final drive that was able to be broke. The very first batch of BSA 440 Victor racing bikes came out with a chain that could be broke if you jumped the bike and had a nearly closed throttle and slow engine RPM when it landed and bottomed the suspension on blacktop. As much as the BSA folks hated to add a couple of more pounds to the machine all later production had slightly bigger final drive chains. I can see there point because the bike was not suppose to be jumped except on dirt.
A master link [properly called a connecting link] is not really all that much a 'weak link'. The pins and side bars are of the same size and material. Unless the application is for a very high speed chain drive [which will almost certainly require special lubrication such as spray or sump] there is no reason to worry about a standard connecting link.
I have run into only one instance where a two wheeler utilizing a chain on the final drive that was able to be broke. The very first batch of BSA 440 Victor racing bikes came out with a chain that could be broke if you jumped the bike and had a nearly closed throttle and slow engine RPM when it landed and bottomed the suspension on blacktop. As much as the BSA folks hated to add a couple of more pounds to the machine all later production had slightly bigger final drive chains. I can see there point because the bike was not suppose to be jumped except on dirt.
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been trying to think of a motorcycle i see one time it was hell on two wheels . like chevy 350 shoved in a frame . i think it was nicked named the widow maker ,some race bike built back in the 60s or 70s . the thing i remember about this thing was the drive line it had this monster motor and a in out clutch . in the way it was in gear or not , they used a saddle harness clamp to control the clutch . they would start the bike lift the rear wheel and lock the front brake . the rider got on and flipped the clutch sending the tire into a wild spin on the stand . got set , full throttle and then let the front brake go . the bike rolled forward off the stand tire hits the tar and your gone . i remember the guy was thinking it was so funny he was putting like 100s of hp throw this chain and it was only rated at 35 hp .now i would think that a full size bike that can do a 100+ mph could hook up much better then any mini bike. just do to weight and size .so unless you have a huge slick and the worst batch of chain ever or running like #25 i dont see how you could be putting that much shock load on one .
i know in the specs chain is not supposed to break but it does .it will only stretch so far.
but i'm thinking your chain alighnment could be off causing your chain to bind and knocking off the retainer that holds the master link together
or the retainer is being installed backwards resulting in the retainer being knocked off.
i like to run rlv chain with a master link up to 15hp and w/o a master on any thing over 15hp:thumbsup:good luck
but i'm thinking your chain alighnment could be off causing your chain to bind and knocking off the retainer that holds the master link together
or the retainer is being installed backwards resulting in the retainer being knocked off.
i like to run rlv chain with a master link up to 15hp and w/o a master on any thing over 15hp:thumbsup:good luck
I have seen the following situation.
Some clutches have the 11 or 12 tooth sprocket with a minimum of clearance on one side. If the connecting link is inserted in the chain with the pins pointing toward the side with the minimum clearance the pins [which are grooved to accept the keeper] will interfere and the keeper scraped off.
Some clutches have the 11 or 12 tooth sprocket with a minimum of clearance on one side. If the connecting link is inserted in the chain with the pins pointing toward the side with the minimum clearance the pins [which are grooved to accept the keeper] will interfere and the keeper scraped off.
Wow thanks so much Old Salt and the rest of you!!! im sorry im so late getting back to my own thread its been a rough semester of college :hammer: anywho im going to take a look at my alignment, its the only thing i think could be causing the problem, im using the stock chain size on the doodlebug which i think is 35 or maybe 38 pretty sure its 35 though. I have tried not using the chain tension thing (sorry to be so vague) and it still seemed to break. Its currently snowing again so il update when i can actually get the chance to take her out and attempt to get it running again.
thanks a million guys you rockkkkk, seriously!
thanks a million guys you rockkkkk, seriously!
Measure the chain for "stretch" to see if it's worn out. Make sure correct master link is used for your chain. Make sure sprocket is not running "out of round" as well as not wobbling. Sprocket bolts must be tightened evenly. Is chain clean/oiled? Is there any frame interference with chain- rubbing anything? Is chain tensioned properly? Is jackshaft true and smooth-running, aligned/oiled?
