440 sleeve scored, options?

[ATVer14]

I took apart my engine last night to make sure everything was in good shape for the upcoming race season, but sure enough it wasn't. I have some scoring on the front of my sleeve (exhaust side) and matching gouges in the piston, a JE 89mm 440 piston. I brought it to the local custom engine shop, and he said that he was going to try and clean up the scoring with a hone because it isn't that deep, and that I could probably re-use the piston if he just smoothed over the gouges. HOWEVER, after doing a few hours worth of searching on this site, I don't really know if this is worth it.
First off, if my engine builder could get this all done, would the cylinder wall be too thin to be safe and would the piston still have the proper clearance?
Secondly, by smoothing over the gouges in the piston, will that weaken or throw the balance of the piston off?
Third, if he did have to bore it to a larger size, Sparks lists a 89.25mm piston on his site, could I use this safely?
Lastly, if it turns out that the hone or bore won't work, what are my options? A new 440 sleeve and piston? But then if this happens again I'll have to redo it all over, so is there any way to go to a 426 or something even though my cylinder is already bored to accept the 440 sleeve, and then I would have plenty of material for overbores?
Thanks in advance for the help.
Kenny

[Wesben]

How about going to a 460 kit ?:devil: Unless you are worried about overheating problems .:blah:

[ATVer14]

Yea, not only overheating problems, mechanical problems, and all the money it costs to beef up the engine for that kind of power, but a 460 is a bit over the ATVA limit to race unless I go to the open class. So I need to keep it under 440. I'm hoping the honeing will work, or else I'm thinking a new 440 sleeve is in order. :(

[twisted threads]

Isnt there any half sizes you can go to?? like 89.5mm or something like that? If it was me I would bore it and put a new piston in there. How they going to know if your running a little over the 440cc (or is it 450cc??) limit any ways?:cool:

[ATVer14]

Twisted- That was what I was wondering. Sparks offers 89.25mm and 89.5mm pistons, but would boring the sleeve out to accept those pistons make the sleeve wall too thin?
And you're right, the limit this year is 450cc, so the 89.25 or 89.5 won't send me over the edge, I think, its the 465 that would, whatever size piston that is. They wouldn't know, but that is the last of my worries, the money involved to get it there is the problem:D

[K_Fulk]

Originally posted by ATVer14
I think, its the 465 that would, whatever size piston that is.


It would be a 92 mm piston.

I would just get a 89.25 bore piston. But if your worried about the sleeve just get a new sleeve. Its gonna cost about the same amount of money either way. But your less likely to have problems problems gettin the new sleeve.

[RED121572]

Actually, youve got the same size motor I do. An 89mm is a 435. If honing wont fix it, bore it out to an 89.5mm...which is a real 440. Better yet, go bigger!!

Good luck and let us know how it works out:cool:

[sleeveslave]

Originally posted by ATVer14

First off, if my engine builder could get this all done, would the cylinder wall be too thin to be safe and would the piston still have the proper clearance?
Secondly, by smoothing over the gouges in the piston, will that weaken or throw the balance of the piston off?
Third, if he did have to bore it to a larger size, Sparks lists a 89.25mm piston on his site, could I use this safely?
Lastly, if it turns out that the hone or bore won't work, what are my options? A new 440 sleeve and piston? But then if this happens again I'll have to redo it all over, so is there any way to go to a 426 or something even though my cylinder is already bored to accept the 440 sleeve, and then I would have plenty of material for overbores?
Thanks in advance for the help.
Kenny

1. No, the cylinder wall would not be too thin. Depending on the extent of honing, it is very possible your piston-to-wall clearance will no longer be proper.
2. Would depend on the extent of the damage. Do you trust this builder?
3. Sleeves made by the big 3 manufacturers are all quite capable of handling the 89.5mm piston. If you aren't sure of the origin of the sleeve, measure the OD of the step and report back.
4. If the hone/bore does not clean up the damage, your only option is to resleeve. Instead of starting with the 89mm sleeve, you could install one that starts at 88. Running a piston smaller than 88 will require a custom built sleeve. Easy to do.

Northwest Sleeve
Tech Staff

[Chef]

After I burnt a 440 piston and scratched the cylinder walls and piston I ran an 89.5 for a while, before going to the 465. It worked fine, probably wouldn't have noticed a change if I didnt change other things at the same time. (Cam, compression, carb parts, etc)

[ATVer14]

Thanks to everyone for all the replies.

Sleeveslave- Can you explain a little more about the "OD of the step," like what part of the cylinder is that (I know OD is outer diameter, but what is the step)? I'm not sure who made the cylinder, but it is one that tapers down to fit into the stock cases, i think around a .0050 wall thickness at the end of the taper, but I'll have to double check. Would this work for the 10 or 20 overbore (89.25 and 89.5 according to Sparks)? I'm pretty sure I'm going to end up with one of these since I only plan on getting another season or two out of this quad before I hop up to a 450r, so there is no need to dump money into a 465 now. Thanks again.
Kenny

[sleeveslave]

Kenny:

Sleeves are "stepped" and not "tapered" because tapering does not provide the necessary clearance for the sleeve and the case from the base of the cylinder to the bottom of the sleeve. The OD at the step of the big bore sleeve averages 3.725 - 3.730". Compare the OD on your sleeve with this dimension. If it is really close, you can run the 89.5 piston. If it is not, let us know what it is and we can re-calculate the oversize situation for you.

The part of the sleeve that you mention is quite thin is not a concern when determining where you can go with over bores. That machined chamfer is to provide easier cylinder/piston installation.

I think you'll be fine with either oversize--I would be very surprised if the wall thickness at the step was insufficient to accept the 89.5 piston. Hope this helps.

Northwest Sleeve
Tech Staff

[ATVer14]

Alright, the hone cleaned it up, HOWEVER, the piston to cylinder clearance is now at 4.5 whatevers (he just put a guage in the cylinder and said it was around 4 and a half, so I'm guessing that is thousandths, .0045). Is this too much clearance, I think I've heard it should be around .002" to .003".
The OD of the sleeve that sticks out past the cylinder, I think that is the step, is 3.605 :huh , significantly different from 3.725. I would only need to run a 89.25mm piston, will I still have enough sleeve for this, or am I looking at a new sleeve. Thanks
Kenny

[pnut420]

Originally posted by ATVer14
Alright, the hone cleaned it up, HOWEVER, the piston to cylinder clearance is now at 4.5 whatevers (he just put a guage in the cylinder and said it was around 4 and a half, so I'm guessing that is thousandths, .0045). Is this too much clearance, I think I've heard it should be around .002" to .003".
The OD of the sleeve that sticks out past the cylinder, I think that is the step, is 3.605 :huh , significantly different from 3.725. I would only need to run a 89.25mm piston, will I still have enough sleeve for this, or am I looking at a new sleeve. Thanks
Kenny

OVERSIZE FOR 440cc BORE KIT +.020"

$219.95 #00314B-HC

89.5mm Forged Piston, 11.2:1 Compression

Oversize for our 440cc bore kit listed above.

INCLUDES: Piston, pin, rings, circlips, headgasket, basegasket

REQUIRES: Must use oversize sleeve provided with any aftermarket 440cc kit.

TRX XR400 440CC OVERSIZE .020" -- $219.95

Powroll has this kit and has been building engines for 40 years so that is who I would go through. Plus it includes everyting you would need. http://powroll.com/P_HONDA_TRX400EX.htm

[sleeveslave]

Kenny:

You are out of options with your current sleeve. You do not have enough wall thickness to go to 89.25. I know you race, but I don't think I would point you in the direction of resleeving with a 89.5 piston. Powroll has great products (and they use our sleeve) but think about giving yourself some room to bore should you need it before the end of the season and prior to the arrival of the new 450.

Northwest Sleeve
Tech Staff

[SnellCRP]

Sleeveslave I just bought a 440 Ross kit with a L.A. Sleeve and I was told by C&D that there were overbores on the sleeve, but when I measured it the piston was 89mm. I don't know if the sleeve can be bored or not. Any suggestions? Thanks.

[ATVer14]

Alright, I kinda figured I was going to have to face the music at some point:D . So you would suggest going with the Powroll 440 kit below, or do you mean going even smaller? That sleeve will fit in my cases without having to bore them out, right? Thanks
Kenny

BORE KIT 440cc

$305.95 #00314HC

89mm Forged Piston, 11.2:1 Compression

Perfect for riders looking for additional torque and smooth power delivery.

INCLUDES: Sleeve, piston, pin, rings, circlips, headgasket, basegasket

REQUIRES: Re-sleeving of your cylinder, rejetting

TRX XR400 BORE KIT 440CC -- $305.95

[ATVer14]

Or what about the IMS/Wiseco kits from Rocky Mountain, they're $70 cheaper. Or isn't that a good choice? Thanks
Kenny

[pnut420]

Originally posted by ATVer14
Or what about the IMS/Wiseco kits from Rocky Mountain, they're $70 cheaper. Or isn't that a good choice? Thanks
Kenny

That would be a good kit also. Im not sure about the powroll piston, but I know that Micky Dunlap can have custom pistons made from Wiseco (sp?) that have the exact deck height for our Ex's, where JE and ROSS are not the right deck height (xr400 piston) and unless you deck the head, it will not be the true 11.2:1 they are advertising and will have an air gap that supposedly creates more heat and robs power a little. So in other works I would call Micky at Four Stroke Tech and ask him what he thinks would be the way to go and he might be able to save you a few bucks. I know he works with powroll on stroker kits so they both could probably give you what you need.

[SnellCRP]

I had TC do my motor in '01 and he actually took .030 off of the base of the jug and used a thin head gasket. I just found that out though. I had a 440 sleeve installed in that jug and the bottom of the thick part of the sleeve was sticking out .030 below the gasket surface. Had to machine it off and will have to clay piston to make sure no piston/valve contact is happening.

[pnut420]

Originally posted by SnellCRP
I had TC do my motor in '01 and he actually took .030 off of the base of the jug and used a thin head gasket. I just found that out though. I had a 440 sleeve installed in that jug and the bottom of the thick part of the sleeve was sticking out .030 below the gasket surface. Had to machine it off and will have to clay piston to make sure no piston/valve contact is happening.

I think I am going to go with the custon made Wiseco piston that Micky has. Both my contact surfaces are good so I don't need any taken off. I just think JE, Ross, Wiseco need to advertise a true compression or state you will not get the true compression unless you deck the head or the base of the jug and use a thinner head gasket. Their kits are the same used in the XR400 but the XR400 has different deck height, so Micky's piston seems alot easier. Even if I go with the custom Wiseco piston, I am still going to clay the piston and check for clearances.

[sleeveslave]

I need to apologise and correct some information.

If the 440 sleeve has a step OD of 3.600 you can use the 89mm oversizes, BUT the wall will be less than .040" on the 89.5 piston.
So Kenny, sorry--if 89.25 will clean up your cylinder that's the way to go.

Again, I apologise for misleading any of you on because of the incorrect dimension I mentioned.

Northwest Sleeve

[ATVer14]

No problem at all, I'm actually really excited to hear that, it will save me a lot of money. I was just about to call FST and Sparks and see what they could do for me, but I decided to check my post one last time. Lucky me! Alright, the 89.25mm will definatly clean everything up, the hone actually got most of it, it was just the piston-wall clearance that was the issue after the hone. Thanks again for all your help, I really appreciate it.
Kenny