padrutt199
Member
- May 22, 2001
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i want to know how many hours ar on your bike before you do a topend rebuild please tell me if its a 125 250 or 500. thank you
how often do you put a new topend in your bike
- Thread starter padrutt199
- Start date
Senior KX Rider
Super Power AssClown
- Nov 9, 1999
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I do my 125 at about 10 hrs. My 310 I let go 25 to 30 hrs
well theres alot more to it than a clean air cleaner.smaller bikes rev more,therefore more friction,more wear.that friend of mine w/ktm is a casual trail rider therefore his piston/rings have lasted 12 years.and yes ive rode that bike and it starts easy and runs good.but that cant compare with some 125A hotshot or a 80A rider,theyre on the gas constantly and if you dont replace parts as needed "ka boom".
marcusgunby
LIFETIME SPONSOR
- Jan 9, 2000
- 6,450
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125 Cr125 6hours on a ring and 12hours on a top end.
Nevada Sixx
Member
- Jan 14, 2000
- 1,033
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wouldnt tear downs be different according to how you ride your bikes?
If you dont slip the clutch alot or scream the engine, i bet you could go a long time on a ring.
If you dont slip the clutch alot or scream the engine, i bet you could go a long time on a ring.
cr125_king
Member
- Apr 2, 2001
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Yes i'd tend to think so. If you dont scream your bike to the moon and run the "poo" out of it, then a top-end is going to last you a little longer. I run my bike fairly hard, and i do my top-end every half a season. I also do my air filter every ride, and when i take my top-end apart, there still in ok shape. When i bought my bike last spring 2001, the last owner had never done the top-end!!!. Thats 5 yrs. When we took it apart it was still like new, We couldn't believe it.:cool:
padrutt199
Member
- May 22, 2001
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- Thread starter
- #11
i had to rebuild my 125 4 times in under 5 months i think i just ride alot though and it cost a lot thats like 600 dollars cause i had to do a full rebuild once too so i was just wondering if my bike wears out really fast i geuss i just ride alot
dheard4992
Member
- Feb 25, 2001
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ring replacement
youd be much better off on my 99 rm250 with a new top end and many extras for 2600
youd be much better off on my 99 rm250 with a new top end and many extras for 2600
nikki
Moto Junkie
- Apr 21, 2000
- 5,802
- 1
125 - a ring every 8-10 hrs and a piston every 15-25 hrs
Everything has always looked fine using this time frame - I could probably go longer with no problems... but it's just "preventative maintenance", keeps things fresh, and my powervalves usually need a good cleanin every 8-10 hrs anyways.
Everything has always looked fine using this time frame - I could probably go longer with no problems... but it's just "preventative maintenance", keeps things fresh, and my powervalves usually need a good cleanin every 8-10 hrs anyways.
According to the manufacturers on a 125 they suggest a new top end every 10 hours. Unless you are freaking Grant Langston, then it is overkill IMO.
The guys that need new top ends every 10 hours has thousands of dollars riding on a single race, so a $100 top-end is basically an "operating cost".
Unless you ride HARD and OFTEN you are not going to notice a 7% decrease in power on your bike over the life of a top-end. For the weekend-spode to go around doing their top-ends every 8-10 hours is a only blessing to the guys at the parts counter IMO. It is a waste of time and cash if you ask me. For a two year old bike to have gone through only 2 set of tires, but had 10 - 12 top-ends done on it is foolishness. I have spoken with a mechanic that toured with the pros and he would save the top-ends that were changed out every 4 races and run them on his bike because they still had plenty of life left in them.
If you only ride 2-3 times a month then you can probably get by with doing a top end on a 125 every 4-6 months providing you do the required air filter and crank-case oil servicing. When your bike becomes hard to start, you might have waited too long, though!:D
BTW - if your powervalve needs cleaning every 10 hours, you might need to re-jet (or you are really getting in more than 10 hrs of riding time!). I just yanked the top-end off of my YZ after 5 months of operation and the piston is in A-1 shape (almost zero carbon build-up) and the powervalve was very clean. The cylinder bore was shiny and still looked like it was just honed. I only needed to run the cylinder under the parts cleaner a couple of times for the powervalve to look like new again.
Disclaimer - when it comes to the care and feeding of my bike I am pretty anal about this stuff. I change the oil every 3 rides (with the good stuff like Solkolene or Maxima) and the air filter gets cleaned every 2-3 rides. I am also cost-conscious though and spend money when warranted. I can not justify popping a $100 top-end in my bike every 10 hours of operation when I only ride 2-4 times a month (and one of those times is a TORO race).
Sorry for the long post - and of course, YMMV...
-jeffd
The guys that need new top ends every 10 hours has thousands of dollars riding on a single race, so a $100 top-end is basically an "operating cost".
Unless you ride HARD and OFTEN you are not going to notice a 7% decrease in power on your bike over the life of a top-end. For the weekend-spode to go around doing their top-ends every 8-10 hours is a only blessing to the guys at the parts counter IMO. It is a waste of time and cash if you ask me. For a two year old bike to have gone through only 2 set of tires, but had 10 - 12 top-ends done on it is foolishness. I have spoken with a mechanic that toured with the pros and he would save the top-ends that were changed out every 4 races and run them on his bike because they still had plenty of life left in them.
If you only ride 2-3 times a month then you can probably get by with doing a top end on a 125 every 4-6 months providing you do the required air filter and crank-case oil servicing. When your bike becomes hard to start, you might have waited too long, though!:D
BTW - if your powervalve needs cleaning every 10 hours, you might need to re-jet (or you are really getting in more than 10 hrs of riding time!). I just yanked the top-end off of my YZ after 5 months of operation and the piston is in A-1 shape (almost zero carbon build-up) and the powervalve was very clean. The cylinder bore was shiny and still looked like it was just honed. I only needed to run the cylinder under the parts cleaner a couple of times for the powervalve to look like new again.
Disclaimer - when it comes to the care and feeding of my bike I am pretty anal about this stuff. I change the oil every 3 rides (with the good stuff like Solkolene or Maxima) and the air filter gets cleaned every 2-3 rides. I am also cost-conscious though and spend money when warranted. I can not justify popping a $100 top-end in my bike every 10 hours of operation when I only ride 2-4 times a month (and one of those times is a TORO race).
Sorry for the long post - and of course, YMMV...
-jeffd
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When I install a new top-end, I break it in, then do a compression test. This is my baseline number. I recheck the compression every couple of rides, and when I have lost 10-15 % of the baseline number, it is time for a rebuild. This usually gives me between 60-80 hours on my 250.
padrutt199
Member
- May 22, 2001
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- Thread starter
- #17
Re: ring replacement
like i said i need to sell my bike first
padrutt199
Member
- May 22, 2001
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- Thread starter
- #18
Re: ring replacement
if i sell my bike and you still have yours i will by it from you
if i sell my bike and you still have yours i will by it from you
- Jun 5, 2001
- 7,538
- 18
On my 92 RM250 I actually went 5 years without a top end change. When I pulled it apart, the cylinder was in great shape and there was minimal blow-by on the piston. I ride about 3 times a month and it ranges from track to trail. When the bike gets hard to start, and after changing plugs, I shoot for the top end. I can't see taking it all apart just to change the rings. You might as well change the piston at the same time. I'm with spanky now, I ride about 60 hours, give or take, before a change on my new 2001. The air filter gets cleaned every other ride unless is was abnormally dusty that day. The gear oil gets changed about every 5 rides, it's cheap and easy.
It's hard to tell when you lose your power gradually because you ride it all the time. The compression test at the time of change is a great idea for a baseline. Thanks Spanky.
Elk
It's hard to tell when you lose your power gradually because you ride it all the time. The compression test at the time of change is a great idea for a baseline. Thanks Spanky.
Elk
- Oct 20, 2000
- 2,969
- 2
Couple of questions re:
Break in after a ring only. Is it advisable for a break in like you would do after a complete top end or just do a warm up and cool down to get the ring to seat?
2nd question may sound anal. How do you guys determine hours on your machine? A 12 minute moto could be much more stressful on a top end than 2 hours of trails. A typical weekend for me would be Sunday racing, 2 practices = 4 to 5 laps each, 2 motos = same laps, total time on bike 48 minutes per week.
Break in after a ring only. Is it advisable for a break in like you would do after a complete top end or just do a warm up and cool down to get the ring to seat?
2nd question may sound anal. How do you guys determine hours on your machine? A 12 minute moto could be much more stressful on a top end than 2 hours of trails. A typical weekend for me would be Sunday racing, 2 practices = 4 to 5 laps each, 2 motos = same laps, total time on bike 48 minutes per week.
- Jun 5, 2001
- 7,538
- 18
From what I understand, when you are breaking in the new top end, it's the marriage between the ring and the cylinder. The piston will follow on it's own, I may be wrong though. It doesn't hurt to break it in the same way everytime, rings only or piston and rings. Like I said before, it seems alot of work to just pull the rings and not do the piston at the same time. Cost saving I guess?
I over estimate my time on the bike. 1 ride, 1 hour. It takes up the slack when I ride trails and also when I ride the track.
Elk
I over estimate my time on the bike. 1 ride, 1 hour. It takes up the slack when I ride trails and also when I ride the track.
Elk
