tecumseh-ohh build

delray

Well-Known Member
Cool stuff! Where did you get the hardened crank sleeve.
I got lucking and was just doing my research on ebay for that and found something that work. crazy thing that the sleeve ID was only couple thousand larger then the crank seal. so i didn't loose my seal area for the flywheel side.
 

delray

Well-Known Member
So does this mean we have to start differentiating between hemi and non-hemi OHH's...? :D

Great looking stuff!
hemi design head would be interesting with 55 degree ports with 30-32 mm intake port runner. that should blow something apart.....lol or just scare the little people when the engine turning over 8000+ rpm's.....
 
I got lucking and was just doing my research on ebay for that and found something that work. crazy thing that the sleeve ID was only couple thousand larger then the crank seal. so i didn't loose my seal area for the flywheel side.
Years ago when I was rebuilding BSA engines for my street tracker builds a machinest BSA tuner friend used to make sleeves like you did to renew the bushing side of the BSA cranks, you would grind down the worn end and heat and press the new sleeve on which had a inside groove and hole to provide oil to the rods. It was a hardchromed hi silicon steel and it stopped wear which used to reduce oil to rods and then left side rod would depart the cases!
 

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delray

Well-Known Member
interesting ole4, was that something made for that engine repair or a universal part that just happen to fit the engine. someone else had mentioned to me over he summer after hearing what I was doing to my motor that they would do this to some older Harley engines. what convinced me to go this route on my flathead build. after running it very hard last spring on a dirt circle track and taking it apart and seeing the rollers and sleeve surface look like it never ran. I knew at that point this was going to be the ticket for me. the only concern I had was the couple thousands up and down play when I assembled my flathead. good thing I just also happen to be talking to someone that was older gentleman that use to build two stroke go karts in his day. first thing he said was that's perfect clearance for those rollers. all that will expand right away when you start it up. you need that clearance in there for sure or the parts could expand and gouge everything up.( that makes sense.) like I said earlier after taking the flathead apart it was perfect still and I have never had a motor spin so easy. funny part I had couple friends ride the bike last summer and both could not believe it did not have any unwanted vibrations. just real smooth high revving engine. that could just also be a good balance motor. also had two different guys come forward and told me that when they ran briggs flatheads they didn't like the ball style bearing on the flywheel side because of the load on the pto side would put a side load on the other bearing and roller ball bearings don't like a lot of side load. causing the bearing to bind little. why this doesn't happen on clone stuff? I thought that was interesting to know. with my needle roller bearing it's kind of hard to create a side load with it being so wide. so that just might be a plus for my little flathead build.
 

delray

Well-Known Member
delray, what is the part number on that flywheel? I've seen it once or twice as well on eBay and may just have one laying around unknowingly.
couple i have found never had a part number to go with them. they are kind of hard to find because they are different from most of them i have seen for sale. there is no casting edges or casting flash on them just really smooth like the one i posted on my italy made engine and like I said earlier the magnets are built into the flywheel and not roll pin in like most are built. making the roll pin setup more unsafe to use because magnets are mounted on the outside of the flywheel and I have seen them with a steel keyway taper shaft casted in the center of them,unsafe too. just to remind everybody this flywheel I am using I would not use it for riding around at high rpm's with a cheap unbalance clutch or even a 20-30 series .this flywheel is way to light for that kind of application.
 
My friend made a run of about 20 of them for the BSA racers. When Warren Sherwood (raced the most career miles at Daytona) passed my friend and I bought out his basement I found a couple of them. They really solved the problem of wear. Prior to that guys were installing a special needle and ball bearing and then converted the cranks to a quill feed to oil the rods like triumphs.
 

delray

Well-Known Member
My friend made a run of about 20 of them for the BSA racers. When Warren Sherwood (raced the most career miles at Daytona) passed my friend and I bought out his basement I found a couple of them. They really solved the problem of wear. Prior to that guys were installing a special needle and ball bearing and then converted the cranks to a quill feed to oil the rods like triumphs.
that would of been a very cool thing to do back in the day. any plans on building other engine like that in the future?
 

delray

Well-Known Member
Are you going to put this engine on the dyno? Looks like it will be healthy.
I do have a connection to dyno the engine with it on the bike. dyno is setup for atv's and dirtbikes…..perfect for a minibike. I personally would want to have a good street tire on the back and run a clutch only so it's more of a direct drive. guy that i know also feels that a torque converter may slip little and create a inaccurate reading and the way my unit was slipping on top end last year....not good. really like to dyno my hs-40 i built with some alcohol in it.
 

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