Can anyone help identify this engine
- Thread starter krygods
- Start date
Flip the mounting bracket at the rear triangle over and see how it sits, or as Curt suggested just re-drill the pivot hole lower. If you can level it that would be best, but as SB says it will run ok like that. Gonna run the shroud right? I have never had much luck roll starting a large displacement FD. You will probably need to be able to start it with the recoil.
i already cut the short piece or flatbar with the hole off, shortened it and reattached it. it sits pretty close to level but it still tilted back. i'm going to try flipping it and see how it sits. yea i'm going to use the recoil starter, i've already put the shroud and the original fuel tank back on. Its raining cats and dogs here as i type so if the rain lets up later this afternoon i'll get out to the garage and get a few more pics as i progress along.
That's a cool idea, I have seen that thread. On one of my builds that used a 5hp Robin flat head I drilled and tapped the head to accept a chain saw compression release. It worked like a charm to pedal start that engine.
Thanks to this thread I've reconsidered using a Tecumseh engine on I bike I had intended to power with a 147cc Jacobsen 2 stroke. Mo betta will be a 5 horse (200cc) four stroke Tecumseh. The build ("kindalikeawhizzer)is located here...
http://motorbicycling.com/showthread.php?t=49177&page=16
Change in plans is at the last and most recent post #160. Now I'll stop high jacking this fine thread with an apology for having butted in with my own doings. Carry on sir, it is coming right along!
SB
http://motorbicycling.com/showthread.php?t=49177&page=16
Change in plans is at the last and most recent post #160. Now I'll stop high jacking this fine thread with an apology for having butted in with my own doings. Carry on sir, it is coming right along!
SB
Here you go its for a briggs but think it should also work for your Tecumseh..........Curt
http://motorbicycling.com/showthread.php?t=27573
http://motorbicycling.com/showthread.php?t=27573
Thanks Curt, but I just bought this one...
http://www.ebay.com/itm/NEW-Husqvar...664?pt=LH_DefaultDomain_0&hash=item2599543548
New made for a Husqvarna chainsaw. $10.00 shipped. No doubt the tap for threading it will cost more than that, but a lot easier than making one, eh? The Harley version is three or four times that of course.
SB
Krygods, we used to use Honda XR-75 carbs on our briggs flatheads, but the NT from a chinadoll works decent as well if you're not looking for max speed & power.
These engines run MUCH better with a real motorcycle style carb as the normal stationary carb designs were not intended for constant throttling use.
These engines run MUCH better with a real motorcycle style carb as the normal stationary carb designs were not intended for constant throttling use.
I will agree an M/C type carb is an up grade. However I don't think even the most ardent throttle jockey throttles any more than a governor with the stock carb. Bog a mower in tall grass and the throttle hits WOT in a flash and just as quickly returns it when it recovers. A properly matched carb in good condition will throttle as quickly as the throttle is opened. A lot of poor running problems stem from carb mixing among engines. Changing venture/ bore size in search if power gains is the biggest culprit among industrial carbs.
All that said, Im with you on carb experimentation, but basic knowledge and skills are a must.
All that said, Im with you on carb experimentation, but basic knowledge and skills are a must.
is this the kind of carb that you're referring to?
http://www.ebay.com/itm/1976-1977-1...s&fits=Model:XR75&hash=item2c663d2ea5&vxp=mtr
if so, how much more difficult is it to position the throttle cable to pull from the top of the carb instead of the side?
http://www.ebay.com/itm/1976-1977-1...s&fits=Model:XR75&hash=item2c663d2ea5&vxp=mtr
if so, how much more difficult is it to position the throttle cable to pull from the top of the carb instead of the side?
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Heres some pics. The original carb was trash from sitting with fuel in it so I ordered a $20 xr-75 carb from ebay. I'm still waiting for the throttle cable nipples i ordered so that i can use whatever kind of cable i want for the throttle. also gotta order some cable housing and cable so that i can make some custom length cables for the throttle and the clutch/lift cable.
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VERY NICE fab work, looks like a kit! When it comes time to ride set the tire pressure and spring down force so the roller is deflected slightly into the tire. On the 2.125 tire I only ran about 30psi. The engine is going to be a torque monster. Will climb just about any hill out there. Depending on the roller size and the ultimate rpm it will pull(4K+ easily) should top 30 or so. Great job!
I have Briggs 5S and 6S they are similar to the cast iron engine you have, but not exactly the same, Maybe it is a Briggs, but anyway I like the DIY work your up to and nice seeing it coming along!
I see you already tapped the crankshaft for the roller. I did a 10-24 thread tap on a newer Briggs 80202-0430 70-80's era engine that was an aluminum design. I just was careful and drilled by hand. It worked for my need to just add extra security besides the keyway/set screw, by using with a flat/lock washers and bolt to use on my centrifugal belt drive clutch.
I see you already tapped the crankshaft for the roller. I did a 10-24 thread tap on a newer Briggs 80202-0430 70-80's era engine that was an aluminum design. I just was careful and drilled by hand. It worked for my need to just add extra security besides the keyway/set screw, by using with a flat/lock washers and bolt to use on my centrifugal belt drive clutch.
What size is the roller? The beauty of a drive like this is you can set the speed ranges just by a roller swap. My calc shows 29.75mph with a 2.5@4000rpm. You have 1/2hp more than my Lifan so turning a big roller is no problem. I ran a 3" @4500 and topped right at 40mph. Was a lot of fun on the flats, however it required pedaling the bike to around 15mph before dropping the clutch the ratio was so high. New rollers are as simple as having/getting the size hole saw for the roller you want, and they are easy to carry/change while on the rode as conditions require.
The roller that I have on the engine right now was made using a 2" hole saw. I think i have a 2.25" hole saw also that I can make a roller with.
