HuaSheng valve lap spring shim

karma1968 · Jul 17, 2010

OK this has got to be one of the better mods on this motor. i lapped the valves and put a washer under each spring. motors back to one pull starts. compression is up 50 percent compared to it was new.
makes it hard to pull start

but i can live with it.

ex valve was burnt and that's without a open baffle muffler. maybe high rpm?

anyway lapping and shimming works.... dance1

http://www.youtube.com/watch?v=FDD2mLKUdc8

http://www.youtube.com/watch?v=6GJ3U2ZvWow

scotto- · Jul 18, 2010

karma1968 said:
OK this has got to be one of the better mods on this motor. i lapped the valves and put a washer under each spring. motors back to one pull starts. compression is up 50 percent compared to it was new.
makes it hard to pull start but i can live with it.

ex valve was burnt and that's without a open baffle muffler. maybe high rpm?

anyway lapping and shimming works....

YouTube - HuaSheng 49cc valve repair

YouTube - HuaSheng 49cc valve repair finished

So you just lapped the valves...didn't grind or replace them? Exhaust valve must not have been burnt too badly, huh? Springs may have flattend a bit from over-revving. Those are pretty cheap replacement parts, but not as cheap as washers I suppose,lol dance1

Thanks for the info!

2door · Jul 18, 2010

You'll want to keep an eye on the plastic cam gear. Increasing valve spring pressure might compromise the cam surface. If you start to see or hear excessive valve lash, you'll know why. Be sure to use a very good lube oil and change it often. Let us know how this works for you after a few hours of run time.
Tom

karma1968 · Jul 19, 2010

on my next oil change ill tear it down have a look. the valve lash is a little bit louder from first start up but after two long rides no change.

this is the perfect motor do do this with. the Exhaust valve guide was also damaged so for me to order and replace the parts i could just go out and purchase another one.

i will make a video when its apart......

cheers

scotto- · Jul 19, 2010

karma1968 said:
on my next oil change ill tear it down have a look. the valve lash is a little bit louder from first start up but after two long rides no change.

this is the perfect motor do do this with. the Exhaust valve guide was also damaged so for me to order and replace the parts i could just go out and purchase another one.

i will make a video when its apart......

cheers

Nice...can't wait to see it! I've gotta split my cases pretty soon here as well, snapped off the oil slinger somewhere down the road. Got a bit over 2000 miles on it so far....still runs great! Cheers.

azbill · Jul 19, 2010

Karma,,,
do you still run without the shroud, and if so, do you think this caused the exhaust valve prob ???

I have 6000 miles on my HS and still have not even pulled the sparkplug, I love this little engine

(why fix it if it ain't broke) laff

karma1968 · Jul 21, 2010

no i ended up putting the shroud back on some time back. im just running it now without.

azbill · Jul 21, 2010

thanks,,,I was curious, that's all

I do like the shroudless look, but can't afford to hurt my engine

NEAT TIMES · Jul 21, 2010

Too Much Valve Lash Is Like A Hammer Beating On The Valve.

Because I Loved My Ford Big Block Late Model Stock Car Motors, I Ran Trw Anti Pump Up High Rpm Hydraulic Lifter`s, Turned The Engine 7200 Max Rpm. With Never A Problem

The Other Guy`s Never Believed Me, Until I Checked The Setting`s In The Pits. Used The Adjustable Solid Lifter Rocker Arms.

Karma, thanks for that info, I am impressed with my titans. Ron . cvlt1

broHSI · Jul 23, 2010

karma1968 said:
no i ended up putting the shroud back on some time back. im just running it now without.

Are you talking about the plastic shroud on the right side with the pull starter?
or
the small metal deflector on the left side over the fins?

I am pretty sure that azbill is talking about the small metal deflector as it
is on in his pics.

Thanks

karma1968 · Jul 23, 2010

the small metal deflector cvlt1

karma1968 · Aug 6, 2010

ok im happy to report all the work was worth it. engine sounds and performs great. one amazing side effect is theirs a unlimited rpm range

witch i never had before. great for riding in traffic. sounds like a 2 stroke heh xct2

i feel if i hold the throttle open to long i could damage or blow the engine easily. im not saying its a bad thing its nice to have the power when you need it

thatsdax · Aug 8, 2010

Yes.. Be Careful as overspeeding the motor can cause a lack of oiling at the con rod. This over heats the con rod and end cap. IT may let go.. Also.. When you get a chance, check your nylon cam lobe for excessive wear since now you have added pressure there. Let us know.. And.. Enjoy the ride..

karma1968 · Aug 8, 2010

i saw a thread a time back about damage to the end cap do to lack of oil so when i had it apart i had the part machined to add a oil hole. so far so good when i open it i will take pictures of the parts.

sorry i forgot to post i did that

2door · Aug 9, 2010

karma1968 said:
i saw a thread a time back about damage to the end cap do to lack of oil so when i had it apart i had the part machined to add a oil hole. so far so good when i open it i will take pictures of the parts.

sorry i forgot to post i did that

karma,
your oil hole might work but a better way to assure proper lubrication of the big end of the rod is to file a small, shallow groove across the inner bearing surface. Honda and the later HS engines all have this oil groove. You can use a small round jeweler's file then smooth any rough edges when you're finished with 400 emory cloth. The groove doesn't have to be deep; just enough to make a gap where oil can get in and out of the bearing during running. Less than 1/16" is enough.
Tom

karma1968 · Aug 9, 2010

ill give it a try.

unior · Aug 13, 2010

2door said:
karma,
your oil hole might work but a better way to assure proper lubrication of the big end of the rod is to file a small, shallow groove across the inner bearing surface. Honda and the later HS engines all have this oil groove. You can use a small round jeweler's file then smooth any rough edges when you're finished with 400 emory cloth. The groove doesn't have to be deep; just enough to make a gap where oil can get in and out of the bearing during running. Less than 1/16" is enough.

would you have a pic of this?

karma1968 · Aug 13, 2010

Saturday is my last day before i strip here down. and do some more work on it. and take pics.

here is a picture of what 2door is talking about. as you can see this idea would work well.

NEAT TIMES · Aug 13, 2010

Karma

That Is For Full Oiling Of The Journal. That Could Be Done Carefully With A Dremmel Tool And May Help.

I`m Thinking Tom Meant A Cross Cut Groove, For More Oil Flow In And Out.

I Have 3 Titans But Have Not Taken Them Apart. Do They Have And Insert Rod Bearing? Or Is The Rod Just Machined For Proper Clearance?

Have Not Heard Of Rod Journal Failure With The Titans. Am Thinking One Member Has Near 50,000 Miles On A Titan !!! ??

Thanks For Posting And The Pic.

A good tip , put a dab of grease or oil under the head of bolts when torquing them. It helps for a more accurate install of the bolt.

Ron . cvlt1

2door · Aug 13, 2010

Ron is right. The groove needs to be across the bearing, perpendicular to the line of rotation. It only needs to be a shallow groove. As I said above, less than 1/16" deep.
Some later Titans came without this extra oiling feature and there were a few rod failures we feel were the result of over speed conditions and the inability of the slinger to get adaquate oil to the rod. Later versions and Honda has this groove machined in from the factory. Ford used to do it with a groove machined in at an angle across the bearing surface, their assumption was that an angled groove carried more oil but we're not talking about high performance V8s here so angling the groove probably isn't necessary. A jeweler's file actually works better than a Dremel because you have more control and less chance of scaring the bearing surface around the groove.
Ron, no, there is no insert. The rods are machined to bearing tolerances of the crank journal.
Tom

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